Similar spec to my HP ultra book (4 GB Ram instead)
Funny how I never had any major issue with any of my computers (now all running windows 7), 1 desktop for gaming and 3 laptops (1 gaming spec one, 1 old one for Uni & this ultrabook).
Only real issue I had was my asus gaming laptop had the GSOD issue, which wasn't a windows problem but a firmwire issue on the graphics chip (ATI 5870m) & a update custom firmwire fixed the issue.
& I just use some basic free A/V software with the default windows firewall, I found the people who always gets random virus (many family friends' computers) are those who just click on any random link without thinking (or don't know better) which in that case even the best security software isn't going to help, unless you restrict user access which will just cause them to rage at you saying that "you broke their computer" or "they can't do what they used to do"