I use FireFox with:
[Please Register or Login to download file] ...you have to learn which scripts to allow but for most sites it just the script with the sites name on and normally only then if you want to use some of the sites features. Here you have to allow Navitotal.com and Yahooapis.com, the other 8 I leave blocked.
[Please Register or Login to download file] ...set it to auto delete contents of sanboxie and have a thin coloured boarder round the edge so you know it's running. Remove the icon for the unsandboxied browser and hide it in the hidden part of the bar at the bottom of the screen so you don't accidentally use the unsandboxed browser (you need to open your undanboxied browser and copy and past safe sites links into it to save them as sanboxie will remove any changes at close. This is a small price to pay for the huge security gain)
After a month, if you don't buy it, it makes you wait 5 seconds? before opening the browser.
I also use a virtual operating system so if I'm stupid enough to DL a virus I can reset my PC and it's gone (free trials last forever with this, reset PC and reinstall, because it is like it was never there. :o )
I use Privatefirewall 7 (free) (it has a process monitor that you can train and use or turn off) . I don't like suites because if it crashes you lose all protection, I've had Comodo and NOD32 suites crash before.
[Please Register or Login to download file] [Please Register or Login to download file] .. neutral site not connected with any software house (as far as I know) and so the results can be trusted.
NOD32 antivirus is what I like and if you can't afford to buy it you can make an e-mail address up and have them send a new 'trial' code there, you can do this every month, you don't even have to reinstall it(the security suite is different and this can't be done)
[Please Register or Login to download file] I also use a router, which helps. All of these could probably be circumvented but you would have to really, really want to infect/access my PC to put all the time and effort into it to do it. I run in Admin mode, which is very bad for security, but I haven't had a virus for over 5 years which is because of the setup I have.
I have never had any security warnings from this site, even when it had problems with the adverts, this is down to NoScript.