For some unknown reason my PC is taking ages to start up, over 5 mins. I have run msconfig and have very few progs running, and hardly any icon on the desktop. It used to open very quickly. Running winXP home, zone alarm and AVG.
You could try stopping some of the programs loading on start up.
Type in msconfig into the the run or search bar. Go to start up tab and untick some of the programs you don't need on start up.
That should help speed things up.
Also, the zone alarm you have, is it just a firewall or do you have zone alarm anti virus as well? Because running zone alarm anti virus and AVG anti virus might be causing you confliction issues, might also stop each anti virus working correctly, so uninstall one and check for viruses.
Check how much memory your machine has, maybe consider an upgrade.
failing that, as a very last issue, you're hard drive could be on the way out - back up your data!
Further to ms-mariams' comment re your hard drive being on the way out, if you haven't got that much free space on your hard drive, then your system will slow down noticeably, especially if you haven't got much space left; i.e.just a few GB.
Altering startup programs using msconfig a bit hit and miss - there are websites giving advice, as I remember someone giving a link here before. Try searching this forum. Only stop one at a time, though. Could be Services slowing things down, but if you haven't changed/added anything recently, perhaps Startup asnd Services are both unlikely culprits. Sure it isn't due to some Zonealarm or AVG updates that have been applied automatically? Although you would think System Restore would sort all these potential issues out if you went back far enough. Still think you should try uninstalling or changing you security software - worth a try.