I've got one of those cards, specifically the 4301 broadcom chip(linksys pci 2.7). If your card is the same, it really isn't hard to set up, but it's a pain to figure out what minor thing is wrong when it's not working/installing right. Show some errors, and someone will be able to help out.
Assuming you're using some sort of drivers Linksys sent you, you might want to try out the forums/software from http://sourceforge.net/projects/ndiswrapper/
Oh, and your root login should be: