Computer Question: Anti-Virus programs?

[Michael Michigan]

I just spent a couple of hours trying to get a bunch of spyware, ad-ware and trojans off a friend of my wife's machine.

She has teen-age kids and her machine had everything, but I think most of it is gone.

With my very limited knowledge, I think now have her set up with everything except for an anti-virus program.

This gal has zero cash, just bought a new house, yada, yada, so I tried

http://www.free-av.com/

But I could not get it to completely load. (I have no idea why)

Any others anyone can suggest?

Thanks.