I think Avast AV is probably the BEST freeware AV program. I gone into several
known "unsafe" websites just to test it out. So far, so good. I think a good AV program is the most important software you can have on your computer. When reloading a computer o.s. it is the first thing I put in after I put in all the drivers.
I try to put it in before I go online (unless I download it from the website-and then the first thing I do after downloading and installing it is to run a virus scan).
AVG used to be pretty good and I used it for a long time. But lately, it doesn't
seem to "cut the mustard". Avira is a little better.
I had a third party firewall in my computer recently and it started blocking all
incoming traffic even when turned off. I had no luck with telephone tech service,
so the technician came out and determined it was the firewall. He said the firewall supplied
by Windows XP is good enough and I don't need a third party firewall. I've
always read that the Windows firewall is rather weak, that's why I installed a third-party firewall. Anyhoo...I uninstalled the firewall and have had no problems since...
Some of these clean-up programs are pretty good. I use Advanced System Care.
It's pretty good and free. Also two good programs you can buy at WalMart are
Fix-It Utilities and System Mechanic. Both are good and cost about $30 ea./year. (unless the price has gone up recently-it's for a one-year's subscription).
Personally, I don't like subscription-based software. I'd rather pay once and pay
$200-300 and use it as long as I want, and in all my computers than pay $30 a
year for each computer. I try to avoid subscription-based software whenever possible, but it's getting more difficult to do.
Periodically cleaning out the prefetch folder will help improve the startup time of your computer.
There's also a program called WOT (Web Of Trust) which I may have mentioned
earlier. It is free and will notify you of potentially dangerous websites. It also has a plug-in for Firefox.
I'm sure these things will keep you reasonably safe.