New to forum. Ramnit infection

Hi, i'm a complete novice with anything techie and am just a basic end user. Please be gentle with me.

The forum was recommneded to me via another forum where we seem to have had a major infection of Ramnit a/b. I think i have fecked my Husbands laptop :cry whilst viewing an infected ad on my forum. It froze and will now not even boot up...any idea as what i can try?...i apologise now for my complete lack of tech knowledge...please feel free to seriously dumb it down.
Thank-you.