I would recommend AVG Free again. I have never used Avast and I stay away from the bulkier products like Norton or McAfee.
If your computers have been hit by malware in the past then I would recommend you reconsider your whole anti-malware suite. An anti-virus isn't enough nowadays. You need the following;
1] A firewall. Firewalls help prevent hackers from getting access to your Operating System. XP's own firewall is much better than nothing but might be difficult to set up as you wish if you do not want to delve into how to code exclusions. There are many good free ones available. If you don't have a firewall running now, turn on the XP Firewall immediately whilst you consider whether to go for something else. The firewall must be running at all times.
2] An anti-virus. Have it running continuously and schedule it to scan your system everyday. Update it daily or every other day. But if you don't, take note when it warns you that its virus definitions are out of date. Don't just do nothing.
3] At least two, but better three, anti-spyware utilities. One of which must be running continuously. That one you scan with once a week or so. The others you perform backup scans every so often. Below are the ones I use;
Windows Defender, Microsoft's own anti-spyware. It runs in the background, and will update itself along with all your other Windows Updates.
AVG Anti-spyware, (formerly known as Ewido anti-spyware). Used as a backup check.
Spybot Search and Destroy. Another backup scanner.
SpywareBlaster, not a scanner, but immunizes against spyware, and can also stop your browser home page from being hijacked.
All of those are free, but they only work if you use them properly, keep them updated, and scan with them.
Keep your Windows Updates up to date.
I would also stop using Internet Explorer. You may need it for Windows Updates and the odd web page that works with nothing else, but IE is the trojan horse of choice for virus writers, spyware and other malware. Instead consider Firefox, Opera, or Seamonkey as alternative browsers.
Stop using Outlook or Outlook Express. They are too closely intertwined with Internet Explorer. Use another email client like Thunderbird.
Again, these are all free.
Never download files from the internet without saving them to the hard disk first, then scanning them with your anti-virus scanner. Never open attachments from an email, but instead save it to disk first then scan it for viruses. Don't trust any attachments, even from relatives or friends. They are usually, without knowing it, the biggest source of viruses.
Stay away from Peer to Peer, (P2P), file sharing. You never know what other people are sharing.
Back up all those files you cannot lose.
If a web site looks suspicious, it probably is. If a web site offers this or that download for free, be wary.
You say you forget to "run this stuff". Would you forget to look left, right, left before crossing the road? You could get hurt that way. If you don't carry out these or similar steps, you could lose all those important files, photos, music and videos on your hard disk.
Mark
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