Bluemonkeyboy - If LimeWire was illegal, then they wouldn't be allowed to distribute it. What some people use it for is illegal. (downloading songs with DRM on em)
iMacs are freakin' unbelievable. I would definitely go for it. It's possible to transfer stuff between your PC and Mac WITHOUT CDs, but it's like... 40 dollars for the cable and software necessary for it.
On this computer, I have 1000+ pictures, which are all about 3 MB each, which comes out to about 3 GB worth of pictures. Most CDs hold about 800 MB. It'd take you hours to burn the CDs and some more time to copy all of the files to your new iMac.
Also, if you're afraid that your iMac might be too slow to play VMK and such, then just partition the drive and install Windows. Bootcamp rocks! (though, I'd prefer to use Mac OSX) I haven't had much problems with Macs/Apples. Mine died, because my brother dropped it and the HD broke. XD It was slow, but that was mainly due to the fact that I loaded it with SO much software, RAM eating programs, and just... Crap. -.-
Apple's Genius Bar is an excellent source for help if your computer ever does something that needs fixing. Also, I think I read somewhere that 1%ish of all viruses are directed at Macs. You'll probably never get a virus.