Can we back up a bit. You say your "XP has fallen apart". You didn't say whether it's XP itself that has failed, or the computer on which you are running it.
If there's something wrong with your copy of XP, it must surely be possible to fix it. Something must have caused it to fail - perhaps adding a new device or installing some new software. If you can identify what that is, and remove it, you should be on your way to a solution. As a last resort, you can always re-install.
If the computer has failed (which is more likely), and if you're sure it's not repairable, you can always buy a new PC and install your existing copy of XP on it (assuming you have the original disks).
My point is that you don't have to face the hassles of switching to a different and unfamiliar system, with all the compatibility issues that will involve - not to mention the learning time. Much better to stick with the system you know, if you possibly can.
Of course, there might be compelling reasons to upgrade to a more modern system. In that case, I stick with my original advice: try to get a Windows 7 system if you can. If you can't, go for Windows 8, but be prepared to make a lot of adjustments in the way you use your computer.