Can't open the application (...) because it is no supported by this type of Mac

If you're trying to open a very old app (OS 9 or earlier), no, it will not open. Tiger (10.4.x) and earlier supported Classic mode, which was OS 9 running in emulation. Leopard and later do not support Classic.

Your Mac is an Intel model. No Mac with an Intel CPU has ever supported Classic. So if this isn't the issue, you'll need to provide more details about what isn't working.

No Mac with an Intel CPU has ever supported Classic.

I take that back. We have an iMac Core 2 Duo, basically the same as yours. One of the few Mac models with an Intel CPU that shipped with its own Intel version of Tiger, which does indeed support Classic. Tiger was never available in the retail version for Intel Macs; PowerPC only.

So I'm guessing that yes, you are referring to old Motorola 680x0 Classic apps. There is no way to run them in Leopard or later, other than than a third party emulator like Sheepshaver. However, that is only the emulator. To get that to work, you need an Apple ROM, which is illegal for you to own unless you also own the exact same Mac the ROM is from. Beyond that, I've read many reports that it doesn't work all that well.

What applications are they? They may have to be run in Rosetta.

Given the OS versions qBittorrent is supposed to run under, it has to already be a Universal, or Intel only app. You shouldn't need to do anything special to get it to run.

Now don't take this the wrong way, I'm just throwing this out as a possible reason. There is a lot of completely legal stuff you can get through torrents, but the vast majority of it is illegal software. This software, no matter how clean a torrent site may claim them to be, are the choice of crooks to load up with backdoors, key loggers, you name it. If you've installed any, or a lot of such software on your Mac, don't at all be surprised it isn't running as expected.

Have a look at this site to check your applications compatibility with Snow Leopard.

Applications compatible with Snow Leopard

In any case, the icon has a bar across and won't start at all.

Hmm, there's no reason the app shouldn't run under Snow Leopard.

Here's one possibility. When you installed SL, did you update it? The latest release on the retail DVD is 10.6.3, but the most up-to-date version is 10.6.8. It is not at all uncommon for apps to require a certain level of updates in order to work.

Go to the apple icon at the top left and choose About This Mac. What is the version number? It it's not 10.6.8, you haven't applied all updates, and that very well could be preventing the app, and others, from working.

The thing is that I am 'torrent virgin', meaning I have never even tried to download a torrent and was told this is the best

In this case... I just want to put [extra] empahsis on Kurt Lang's comment with respect to being cautious about torrents. It is a great way to distribute large files (especially for small developers who can't spend tons on bandwidth), but a huge percentage of the files you may find on torrent search sites contain viruses or other malware. Mind you, I'm talking torrent search sites, not torrents in general. I get most of my linux distros via torrents, but those torrents are actually posted on the respective linux websites (along with other download options such as FTP and HTTP). You shouldn't trust downloading torrents from untrusted sources any more than you would anything else. Anyone can create a torrent and put it out there calling it whatever they choose. For example, somone can create a torrent called "Office 2011 for Mac", but infact it is a small program that will start wiping your drive once you launch it. That of course would be an obvious problem. They can also be much more sneaky by providing you with a workign copy of Office 2011, but with additional code inserted which can get private information or pretty much do anything the programer wants without you ever knowing about it.

Kurt Lang wrote:

No Mac with an Intel CPU has ever supported Classic.

I take that back. We have an iMac Core 2 Duo, basically the same as yours. One of the few Mac models with an Intel CPU that shipped with its own Intel version of Tiger, which does indeed support Classic. Tiger was never available in the retail version for Intel Macs; PowerPC only.

So I'm guessing that yes, you are referring to old Motorola 680x0 Classic apps. There is no way to run them in Leopard or later, other than than a third party emulator like Sheepshaver. However, that is only the emulator. To get that to work, you need an Apple ROM, which is illegal for you to own unless you also own the exact same Mac the ROM is from. Beyond that, I've read many reports that it doesn't work all that well.

Kurt: This is the first I have EVER heard of an Intel Mac running Classic natively, without emulation (and I have done quite a bit of research)! Please reconfirm that this is correct, and if you can reconfirm it correctness, you might want to let the researchers noted in the two links below know about these abilities.

Also, your statement regarding Mac ROMs is too broad and overly restrictive. The emaculation link below indicates a method for extraction of Classic Mac ROMs from an active Apple download link for a ROMs update. I just tried the link last night and it is still active.

I always caution those who make such legal pronouncements to exercise caution; as they tend to keep users from solutions that are otherwise legally available. And I am sure that is not your intention:

http://www.emaculation.com/doku.php/...mac_os_x_setup

and here is some additional information on SheepShaver:

http://www.everymac.com/mac-answers/...ntel-macs.html

I have had considerable success with SheepShaver, running this version of Risk II for the OP of a post on another forum as well as being able to access legacy MORE and WordPerfect files in my archives:

[click on image to enlarge]

I had exactly the same error message when I tried to install the latest version of HandBrake last night: a bar across the icon, and when I clicked on it, I got the error message. HandBrake's site doesn't say clearly which OS and what CPUs apply to which version.

Please reconfirm that this is correct,

It is not. Checked the installer disks, too. No Classic. Which makes complete sense since you'd not only be emulating the OS 9 environment, but also a PowerPC CPU. I could have sworn it was there, but I must have been thinking of the G5 tower I sold sometime back.

Also, your statement regarding Mac ROMs is too broad and overly restrictive.

Well, that really depends on what you read and where you read it. This is the most common description I've read, but hardly the only one.

I just tried the link last night and it is still active.

Yes it is, but that doesn't make downloading a ROM legal. Anymore than it does to download illegal software. Read the page on the site you linked to about the ROM guide.

Note that one of the first things they tell you to do is purchase an old Mac. Then use the appropriate software to make an image of the ROM on that Mac. So yes, if you're going to legally obtain a ROM, you need to own the Mac you are acquiring it from.