Hi Tech,
I agree with the thesis that just a single resident free av-solution is not enough to have full "layered protection".
I would state that using a full security suite and have parts of it disabled (because it works better
) is giving nearly the same overall results of the total free resident solution.
I also would state that if you're aware what layered free security suite to select from free components this can be/mesan an advantage over the single all-in-one suites, because you have a smaller vulnerability window (varying detection spectrum), the various products detect differently and over a much broader scale of malware- so decent free resident av solution, a nasties blocking solution (SpywareBlaster), specific anti-malware solutions (MBAM, SAS, Windows Defender), temp and other cleaners like ClearProg, in-browser security extensions, probably an in the cloud solution" like ImmunetProtect and you are done, learn a bit of SafeHexing and update and patch fully(use Secunia's solution to that problem or SecBrowsing extension in GoogleChrome for plug-ins and you are ready to go without a fear to have missed something. The firewall I would have is the Windows Vista one (make it dual way) or I used ZA free,
and not to forget make XP SP3 more secure with MS's EMET tool, it is great,
polonus