Wndows media player to Apple Itunes

I have ripped quite a few CD's to my external hardrive using WMP11 as my library. They are ripped in Windows Lossless format. I want to purchase a new computer and was thinking of switching to Apple. Would this be an easy transition. Can I hook my external to the Apple and play music off it and use the Itunes setup or would this be to complicated to do. Should I just purchase another Windows PC.
Mine is the last of of there product line that has not changed processors, G5 to Intel Dual Core. It's not PC compatible nor do I want or need it to be. My Son has a new MacBook laptop with the newer processor. Other than hardware options I can’t see a difference. If your are not familiar the new/older mac’s below is a link the apples G5 page. Check out the spec’s and the way the case is engineered and constructed. The darn thing is built like a BMW. Very impressive design.

Vegasears: As you say, Macs can read a PC-formatted hard drive--and that includes a lot of older Macs, not just the new Intels. But that's not Bodine's problem. His problem is that his music files are encoded in a Windows Media format, and iTunes on a Mac cannot read those files, as far as I know. That's why he needs to find some sort of conversion software.
Smart Audio Converter doesn't appear to support Apple Lossless. But the one I mentioned above, dBpowerAMP Music Converter, might.
I was talking to a saleman at Comp USA and he said that the mac would be able to read the windows losslees file and that I-tunes would be able to convert it to Apple lossless. I don't know if he was being honest or just said that to make a sale.I guess I-tunes will create a music library once it reads the file.