Q: still can't get el capitan

Upgrade to OS X El Capitan - Apple Support

Scroll down to How to get El Capitan

The link in the first bullet point will take to you to the App Store download.

That will get the full installer downloaded to another Mac. You can then use DiskMaker X to create a full, bootable USB installer of El Capitan to get it installed on the Mini. You'll need an 8 GB USB drive.

Don't use iTunes. Use the link I posted, which will take you to another web page. Then as my post states, scroll down to click on the link, get El Capitan in the App Store, in the first bullet point. That will automatically launch the App Store on your Mac and load the El Capitan download.

Actually, to make it simpler, I should just post the App Store link:

get El Capitan from the App Store

the version on the app store said it was for someone that was using snow leopard

Actually it's either. For Snow Leopard users who first have to install El Capitan before upgrading to Sierra, or anyone using Lion through Yosemite. As noted at the top of the page I linked to:

OS X El Capitan remains available for Mac computers that can't upgrade to macOS Sierra, or that need to upgrade to El Capitan first

Someone may have given, or sold the Mini to you with El Capitan on it, but that's not what it shipped with. It should have been restored to its original OS, which is Lion, 10.7.x.

The good news is you can do that. Turn the Mini on and immediately hold down the Command+Option+R keys to boot into Internet Recovery Mode. If you choose to install OS X, it will likely try to reinstall what's on the hidden Recovery partition, which would be El Capitan. However, you can't do that since it will ask for the Apple ID used to purchase it in the App Store. You don't have that information.

Instead, go to the Utilities menu at the top and launch Disk Utility. Click on the far left name of the physical drive so you get the Partition tab at the right. Click on Partition and change Current to anything else. If there's only one partition on the drive and that's all you need, choose 1 Partition anyway. If you don't, Disk Utility won't create a new partition map and the old hidden Recovery will still be there. Underneath the partition layout graphic you will also now be able to choose the Options button. Click that and make sure GUID is selected. Click OK. When you click Apply after making these changes, it will wipe everything off the drive, which is what you want it to do.

Exit Disk Utility. Now choose to install OS X. With what is now a bare drive, it will reinstall the original OS from Apple's servers. You will of course need an Internet connection. Either use a wired connection (preferred for this), or click the wireless icon at the top right to connect to your router.

Once the original OS has been restored, you can then continue on with installing El Capitan.

A 2011 Mini should have shipped with Lion.

It sounds like you only held down the Command+R keys, which would explain why Disk Utility couldn't dismount the drive. A Command+R startup boots to the hidden recovery partition on the drive, making it impossible to dismount the drive out from under yourself.

Try again, making sure to hold down Command+Option+R. If that still doesn't work, it may not be a 2011 Mini. Either that, or one of the very last to ship with Snow Leopard.

One way to check is to enter the Mini's serial number here. Then click the Lookup button. The site will then load the page for your exact model Mac. Please post a link to that resulting page here.

I'm sorry but i guess i got things mixed up with you.

Oh! Duh! No, the confusion was mine. You did clearly state you were trying to get a system on an older Mac. Let me try again.

Okay, a 2009 mini will not have the ability to boot into Internet Recovery Mode (Command+Option+R) at all, so skip that whole thing. A Command+R boot will work if Lion or later is installed since it will create a hidden Recovery partition. As you've found, you can't truly wipe the drive from there.

While it's possible to install Lion or other later versions of OS X on the 2009 mini, the new owner would be in the same situation I mentioned earlier. If they were to boot to the Recovery partition to reinstall the OS, they won't be able to since it will ask for the connected Apple ID used to purchase that copy.

The 2009 was right between OS upgrades, so some came with Leopard 10.5, and others Snow Leopard 10.6. What you really need is, preferably, the gray system disks the 2009 mini came with. Insert the first disk and restart. Immediately hold down the C key to boot to the DVD. From there, you can follow the same general instructions above with Disk Utility to completely wipe the drive and then install the original OS. Make sure to include those gray disks with the Mac.

If you no longer have, or can't find the original gray disks, you have two options. One is to call Apple and provide them with the serial number of that 2009 mini. If they have any left in stock, you can then purchase replacement gray disks. General cost for both disks with shipping is about $40.

Or, the other choice is to purchase a retail 10.6.3 Snow Leopard disk directly from Apple for $20. Since the version of Snow Leopard that shipped with some 2009 minis was 10.6.1, the retail disk will work. The only downside is that it will not include the bundled iLife software, such as iDVD, GarageBand, etc. With this disk, you would again boot to the DVD and use Disk Utility to fully wipe the drive, then install Snow Leopard. Make sure to include this disk with the Mac so the new owner also has a way to wipe the drive and sell it with a legal, and restorable copy of OS X installed. It's not much use to you otherwise anyway.

The only reason the Mac would bypass the CD/DVD drive is that it isn't working, so it goes on to the next bootable choice it can find. So yes, you would need to use an external DVD drive in order to boot to the original disks.

It also may be that lens for the internal drive is just really dirty. There's cleaning disks you can get for that at Best Buy or similar stores. It's just a CD/DVD with a brush glued to the surface. You put the disk in, which the drive automatically spins to read, and gets the lens brushed off in the process.

The drives can also die partway. That is, the laser that reads CDs still works, but the separate laser for DVDs has died. So there's that possibility, too.

But anyway, if you have one on hand, plug in an external USB DVD drive and boot to that. If you don't have one, they're pretty darn cheap. A drive that only reads (no write capability) from various manufacturers are under $12.

All i can say about the super drive is that i was burning and watching dvds in it just before i tried the snow leopard thing.

That's good to know. It eliminates a physical problem with the drive as a cause. Check the disks then. Is the non-printed side dirty? Full of fingerprints? Heavily scratched?

I read online that a lot of people were having the same problems and that lion etc. did not support the superdrive.

That simply isn't true. There would be no reason in the world for the OS to refuse to use the drive. Not only that, when you restart, there is no OS at all in control of anything. The Mac is initially running off the boot ROM. It then passes control to the VRAM, which is the point where the Mac searches for a startup disk. Lion, or any version of the Mac OS can't interfere with anything during this process. It hasn't even gotten that far yet.

At this point, knowing the internal drive works, I can't say why the Mac would be refusing to boot to the DVD, or even keep the disk in the drive.