mac newbie with some questions

I just got a new ibook g4 1.07ghz with 512 of ram 30 hd and i love it,being a pc user for about 8 years this is a big change for me.The problem is i'm not being able to open .exe apps that only open on wintel machines and a few file sharing programs like kazza etc.....my questions are..1]will virtual pc 6.1 resolve this problem?
2] is 512 or ram plenty to run virtual pc? 3]what settings should i make on the ibook to improve virtual pc? 4]what maintanance and security utilitys do you guys recommend?

exe files are pc/windows only. kazaa likewise - though I have heard about other file sharing apps. for maintaining you can use Mac janitor from version tracker or the terminal to do manually. Post again if you want those step or search for my previous post on crons Welcome to Mac!

for filesharing use acquisition.

or limewire