[I can go and get a magazine with a Linux CD on it? And if I have to wipe out (re-format), my hard drive, I can install Linux instead of Windows XP.]
Yes

[If I get a laptop, buy a router, connect the whole thing.... and this thing comes back on my computer, DOES THIS MEAN IT WILL INFECT MY LAPTOP?]

If you don't share any files between the computers there should be no problem

[And how come (after last week), every time I want to come on these boards I have to type in my user ID and passwords. I tried clicking on "remember", but it always prompts me.

Does this have something to do with the anti-spam thingee??]

possibly it could be related to it but I'm not sure