How do you no what websites have viruses and what ones dont have viruses?

I would recommend using a site adviser that will tell you if a website is safe or not and if its links are safe or not and if its download and linked downloads or safe or not, i would suggest you use mcafee site adviser.

How do you no what websites have viruses and what ones dont have viruses?nortonantivirus

you don't, so don't download things unless you want to take the chance

How do you no what websites have viruses and what ones dont have viruses?spyware

you dont..so after downloading something check with virus scanner befor running it
Nobody knows until the computer gets a virus. But sites which are most visited may have it. That's why I never open porno and sex sites, rarely watch and download movies.

I trust cNet, filehippo, Microsoft, Dell, etc. when I need to install a software.

And what is important, I run Ccleaner and Ad-Adware very often, so that I can always check what's going on in this field.
Keep away from porn. Steak %26 cheese is a safe porn site. don't download, unless you are sure.
You really can't tell but a good rule of thumb is to stay away from free online movie sites, porn sites, and other questionable stuff. Also, don't click on ads.

I've seen that SiteAdvisor software before also and it is pretty cool.
This can help.

http://www.siteadvisor.com/