Norton 2007 renewal - recommend free alternative

I've browsed the various threads and tech help here including the free download lists and key posts but as there are a lot of combinations, for fear of getting the wrong combination I'd appreciate some clarification. I've used Nortons Int Sec for years. the 3 months trial on latest PC is nearly up. Am getting the feeling that people are not too enamoured with Nortons. As a replacement for Nortons on a stand-alone desktop running XP am I correct that the followowing would be a good alternative :-
- AVG for anti-virus
- Spybot S & D for spyware/ads
- Firewall - just use XP or ? Zonealarm

Some people seem to have 4 or 5 different programs doing all the virus & security now. Would I be as well to renew Nortons and stick with the one program to do all rather than loads of different programs. Thanks in advance.

That combination looks fine to me; it's what I use anyway (with the standard Windows Firewall rather ZoneAlarm).
Occasionally I've also run AVG's anti-spyware program, but I've never seen it find something that SpyBot hadn't...

Thanks for that DrM.

Avast anti virus.
Comodo firewall - AFAIK the Windows firewall only offers one way protection whereas Zone alarm and Comodo both offer two way protection.
Spybot.

Something I forgot, where do these fit in relation to Anti-Spam. NOrtons had in inbuilt.

AVG has antispam.

Run a mile from Nortons.