Oh yes that would be a good idea. One question?
Do you have the original system discs for your iMac? If not you should order a Replacement set from Apple as at some point you will need them. They have the iLife apps included which aren't with the retial Snow Leopard upgrade DVD. Without those original system discs you won't be able to install any of the iLife apps without buying them from the Mac App Store and not all of them are still available. iDVD and iWeb are no longer offered by Apple for for purchase. But once installed from the orignal system discs you can update them to the most current versions for free.
No need to do a clean install. Just install Snow over Leo. That way, you won't have to reinstall all your apps from scratch, plus your user data again.
My current Snow was installed over Leo, which even included a migration from Tiger. No problems.
Again, make sure you have a backup of the Leo. Just in case.
iOS-like refers to features and the user interface which come with iDevices, such as iPad, iPhone.
I disagree with the above statement. With any operating system upgrade it is always best IMHO to do a Clean Install. I have followed that rule for years on both Windows, when I used Windows, and OS X and have never had problems like you see posted on these forums after every new version of OS X comes out.
The one time I did upgrade a OS over the top of the older version was with Windows many year ago and it was nothing less than a disaster. From then on I have never done that, with either OS, and have never had problems like I had doing the over the top upgrade.
You can make a Time Machine backup of your current install of Leopard then wipe the drive and install Snow Leopard clean then at first boot use the Setup Assistant system to copy over your User Account, Files, Settings and Apps from that TM backup. That is what I do with every OS X upgrade and it has worked out very well for me over the years.
I recently installed Mountain Lion over Snow to an external partition, with zero problems. Everything was right where I needed it to be. (Of course, my older PPC apps no longer worked, so I just removed the most space consuming of those files.) That means ML came by way of Leo, using Setup Assistant to a new Mac (with Tiger applications previously migrated using Migration Assistant to the Leo) through Snow, then to ML.
And you don't use Setup Assistant for this. That's only available on the first boot of a new Mac. That would be Migration Assistant.
If the OP has a backup/clone of the Leo to restore, there is little risk in doing it this way.
The disaster you mention was with Windows, not OSX.
And I would go with a clone, not TM, because it's far simpler to restore, and TM in Leo was much less reliable than it has now become...maybe.
I was in the same situation as you. I had updated my G4 laptop to an esrly 2008 24" iMac 3.06Ghz Core 2 Duo with 4GB RAM. I installed CS3 Master Colection on it too.
I upgraded to Snow Leopard a few years ago to be ablew to access the App Store. There were no problems. Everything ran great, even CS3. I did lose iLife but it didn't matter because I had CS3, and Libre Office. Never uased them anyways.
About 6 month ago I upgraded to Mountain Lion, wanting to get a newer OS before 10.9 out of fear it would break Final Cut Studio.
Again everything was great, no slow down and CS3 still worked fine. I would use Photoshop, Illustrator, After Effects, and pretty much everthing in Master Collection.
I upgraded to Adobe Creative Cloud about two months ago at the discounted rates of 29.99 per month, with my CS3 license just to check it out. That worked fine too.
My 500GB hard drive died about a month ago. I installed a 1TB HDD myself. It was actually very easy, took about 45 minutes. I did a clean instal of Snow Leopard from the disc, then back up to Mountain Lion. System actually ran better after the clean install. I guess due to all the years of materials and apps going in and out of the old HDD.
When Mavericks came out and Final Cut Studio seemed compatible (other than breaking Qmaster) I upgraded to it. Everything again worked fine. Although I didn'y like the fact that I could no longer snyc my iphone contacts & calendar with USB. They forced you into the cloud for that now. Don't know if that matters to you.
That being said. Yes you can do pretty much any upgrade with your 1 year newer imac, I've done it on my 2008.
The question is what features do you want/need. I personally like CC for now for access to all the apps.
The CC pricing ain't too bad if you compare to the Master Collection which cost about $2400.00. with the discounted first year it'll takes a little over four years monthly pricing till you reach the $2400.00. If you aren't going to use pretty much all the apps I'd stay with CS6.
So, it's up to you. If you do want to go ally the way to 10.9, I would wait for the bug fixes. You could even stay with Snow Leopard if that's all you require.
Just figure out what suits your needs.
FYI: I installed my old CS3 design standard on 10.9 and it worked fine too.
Just because you were successful in doing an over the top upgrade does not mean everyone will be or that the OP of this thread won't be. Just take a look at all the posts surrounding upgrading to Mavericks over the top of Snow Leopard, Lion and Mt Lion posted on these and many other mac forums.
But in my honest opinion, from years of experience, it is best to do a clean install.
For one BIG reason if nothing else. If you make a Time Machine backup just before you do the upgrading of a newer OS no matter how you do that upgrading if anything goes wrong you can always restore your system to the state it was just before the Dung Hit the Wall.
And, unlike going from Snow to Mav, going from Leo to Snow is not a big jump. YMMV. It's so much more straightforward and much less work to upgrade directly.
Kath: If it doesn't work out, which I think is unlikely, if you have a reliable bootable clone (using Carbon Copy Cloner, Super Duper, or even Disk Utility Restore) it's a simple matter to just reverse clone and you are quickly back with your original Leo intact.
You asked the question. I can, or anyone on this forum can only tell you what they've personally experienced. It's true with anything here, YMMV.
For me it worked. If it didn't I'd have mentioned that too.
I don't use TM, but from what I can tell, a TM system restore is not so straightforward. And, again, I'm not so sure I would trust TM in Leo, which was the first version of TM that Apple released, and it is has a reputation for many complications and failures.
Did you even read that page you posted a link to?
From a TM backup of Mac A restored to that same Mac A all is good.
From a TM backup of Mac A and try to restore to Mac B Things "CAN", not always, go wrong.
I've used TM for years with no problems. Kind of like you with the Over the Top Upgrades. YMMV.
Thanks for all of your advice and opinions. I appreciate it.
and yes, I do have the original system disks that came with the computer.
I am going to start by upgrading to SL and then I'll take it from there.
Oh, and to answer your questions Posthumous,
I mainly use Illustrator and Photoshop. I will be using iphoto, imovie, and some of the others that come standard with the mac. I also am online alot. but as far as Adobe CS goes, its just PS and AI that I use.
I'm not very interested in syncing my I phone, calendar or anything like that either.
I was thinking along the same lines as you...let the bugs get worked out and stick with Snow Leopard and CS6 (if I can still get CS6...I dont know if upgrade can still be purchased at this point?)
Thanks for your advice, your situation seems very close to mine and that's what I was looking for.
I do love this imac even if it's 4 years old, and I don't want to bog it down unnecessarily.
You can still get CS6, but it looks like there's no longer a discount for current CS users.
For Photoshop and Illustrator you can get by with CS6 Design Standard. It's $1299.00, but you can find it on EBay for around $900.00. Still expensive, but saves $400.00.
If you want the latest versions of iPhoto or iMovie they're $14.99 each.
I know what you mean. I love my five year old iMac.
Adobe has an offer for current CS3 & up licensed users to get it for 29.99 per month with a one year contract. Goes to $49.99 after a year. You may want to do the 30 day free trial and see if you want the new functionality. You may find out you're happy with CS3. If you do decide you want it wait till the last day of your 30 day trial so you get 13 months for the price of 12.