I did this a couple of weeks ago, repartationed my drive to winXP/mandrake. As far as getting the files on your box and have it up is pretty simple, most novice windows users could do it. The hard part comes in with hardware. In my case, ive found that because my hardware is so new there isint much support(drivers) for it out there. What your gonna give up with windows is a lot of ease of use, Linux IS better hands down(1000s of times more stable,much faster), but its not quite as simple as going do a website and double clicking an icon. Often source has to be made and config files have to be edited by hand. Its not that its hard, just more of a pain in the ass. If i were to suggest a flavor.... I just finished a course and the prof taught us redhat(got an A ). I went home and decided to put linux on my system but got mandrake to see which one i liked better. Mandrake gets my vote. I would suggest that you buy a good book. If you really want to learn it then do as much as you can using the console, and find a book that focuses on that. Ive actually found,after some pratice with it, that for most things i prefer the console.

as a side note if you use this machine as any sort of server be very careful to make sure that its secure, our prof in the class actually taught us how to hack just to show us how insecure everything is. You might check into (if they make them for mandrake)logsentry, portsentery, IPtables, tiger, and tripwire.

Hope this helps feel free to ask any question you have