Thats all fine and good what you say but how did that garbage get on fallout3 nexus to begin with?
I'd bet that you already had it on your computer, it just happened to do something new or kick in when you were on the site by coincidence. If you didn't even know that antivirus 2010 wasn't legit, then perhaps you aren't as internet savy as you'd like to believe. I'd suggest you
1. Do some actual research and use a
real antivirus program.
2. Use Firefox, and download Adblock and NoScript.
3. Learn how to use all of the above.
I've been going to the Nexus for years and years, counting from before when it was the Source and I've never, ever, even almost gotten any malware from it. On the off chance that the site was compromised, and you did in fact get some kind of virus from it, it is due to you not having taken proper precautions, and could have happened on any site on the internet. It's a simple fact, I'm sorry. The amount of damage a virus can do without you being fooled into clicking on things is extraordinarily minimal, unless you have some very strange settings allowing full on internet [censored] or already are infected.