r u using trial editions of all these : nav, panda, mcafee ? then the 'autoprotect' will disable after the trial period is over. but yes, it shud not b hapning in a day or two ! even in case of avast u have to get the free serial and enter/register it !
if that is the case, i think ur registry may be all junked up with all these uninstalls. if u can, reinstall xp just this once and intall avg free av from
www.grisoft.com U wont need a serial for it too ! also instal avg anti-spyware freeware from the same site. update both and scan UR entire PC with each of them, in SAFE MODE.
if u dont wish to uninstall, the run
www.ccleaner.com and clear ur pc junk with it. scan ur full pc with ur av and as in SAFE MODE. also post ur hjt logfile to see if there really is any malware infection.