Hard drive failing, need new Mac, how can I keep iTunes 10.7

Question

I've got a mini mac, ca. 2009.  The hard drive has begun to fail, and the external monitor is also beginning to go (once all-black screens is now mostly pale grey. 
I have 75,000 songs on an external drive.  I tried iTunes 11 when it came out, and had to roll back to 10.7 because iTunes 11 is simply not capable of managing a large library.  Lack of multiple screens alone is enough to drive me away. 
When I asked at the Apple store if there is any way to keep iTunes 10, they laughed in my face, then got the Apple-knows-better-than-you tone and said there is no way to use an "inferior" version of itunes anymore.
Is there any hope?

Answer 1

Any new Mac will come with the newest iTunes installed.  Now something I don't really know much about but could be an issue is according to what I have read iTunes is now more intergrated into the system of the Mac.  It used to be a pretty much stand-alone application which you didn't even have to install.  How integrated I don't know.  It may still be possible to delete iTunes using one of the many reverting back to an older version method posted here. Using older operating system components is not something you can do though, since they may well cause instability in a computer that was designed with a newer system in mind.  However, I don't know if iTunes is really that much part of the system.
Realize also that you will be forced to upgrade should you ever buy an i-device since those require the version of iTunes current when you make the purchase.
Here's a downgrade post I had in my archives:
Back up your computer first, in case the unexpected happens
Here's a step-by-step method and you may find it easier to follow than alternative methods I have posted below.
Downgrade iTunes 11 to iTunes 10.7 - http://www.emacconsulting.com/apple/itunes/downgrade-itunes-11-to-itunes-10-7/
If the above does not work, or you want to do it without Pacifist, or you want to know what is actually going on when downgrading, or you encounter error messages, here's more details:
Quit iTunes.
Get iTunes 10.7 from http://support.apple.com/kb/DL1576 or the direct download link at:  http://appldnld.apple.com/iTunes10/041-7195.20120912.d3uzQ/iTunes10.7.dmg
Do a few preparatory steps by making sure all iTunes components are not running and cleaning old files.   See https://discussions.apple.com/message/20475394.  Do steps 3 and 4.  Steps 6-8 may be also useful but I don't know if they are essential.  Some of the other steps are not necessary, duplicate steps listed later in my post or are perhaps even unhelpful in the process.
Replace the iTunes 11 application with iTunes 10.7.  Simply dragging the application to the trash may not work. Lion (OSX 10.7) and newer systems have iTunes integrated into the operating system and deleting is a bit more involved.  Two ways to do this are:
1.  (Easier) Use the shareware Pacifist utility (http://www.charlessoft.com/) to install iTunes 10.7 including all associated system files. Details at http://forums.macrumors.com/showpost.php?p=16400819&postcount=6
2. (More work) Check this reference on how to delete the iTunes application itself:
    Delete iTunes in Mac OS X 10.7 Lion - http://osxdaily.com/2011/09/13/delete-itunes-in-mac-os-x-10-7-lion/
    After deleting the application there may be other files that need downgrading too. See the note about error -42408 at the end of this post. You may want to tuck these away somewhere safe until you have completed the installation of iTunes 10.7.  I have not tested this but ideally if newer versions are not found then the installer will put in the old versions. This may include these files in /System/Library/PrivateFrameworks/ which apparently get updated by iTunes 11:
AirTrafficHost.framework
CoreFP.framework
DeviceLink.framework
iTunesAccess.framework
MobileDevice.framework
After doing one of the two procedures above you will have to rescue the most recent old iTunes library from your iTunes > Previous Libraries folder. Rename it "iTunes Library.itl"  and replace the existing one in the iTunes folder. A newer version of iTunes irreversibly updates your library file so you have to replace it with the old one or you will get an error message. Note, this will revert your library to the version at the time of the upgrade and you will have to update any changes made since.  See:
https://discussions.apple.com/message/20401436 - turingtest2 11/2012 post on rebuilding empty/corrupt library from previous iTunes library file after upgrade/crash.
iTunes: How to re-create your iTunes library and playlists - http://support.apple.com/kb/ht1451
Other issues:
- https://discussions.apple.com/message/20432309 - solution to mobile devices saying they need to be restored after downgrading
- If you encounter error -42408:
iTunes: Advanced iTunes Store troubleshooting - http://support.apple.com/kb/TS3297 > Specific Conditions and Alert Messages: (Mac OS X / Windows) - including specific error codes.
- Persistent "Show in iTunes Store" arrows after downgrade - https://discussions.apple.com/thread/4567064