After I used PerfectDisk 7 to defrag C drive, windows xp hangs at startup for about 5 minutes. I logon, all startup programs installs, but when I use explorer, the torch appears and stays there for 5 minutes before all my partitions appears.

Use system restore to go back to the last restore point. http://computervitals.com/

but it was done a while ago, and trying to find a fix, as I have used perfectdisk before, it's just I changed my motherboard, graphics and cpu. So it must be something simple?

Explain what you have done. Karnak has left the building. http://computervitals.com/

Windows XP Pro SP2 was fine, then I used PerfectDisk 7 Build 46 to defrag C drive using online smartplacement and offline defrag directories. Now XP hangs for about 5 minutes, and if I use explorer and click on my computer, the torch appears looking for my partitions and after about 5 mins it finds them and I can use the computer.

"but it was done a while ago, and trying to find a fix, as I have used perfectdisk before, it's just I changed my motherboard, graphics and cpu. So it must be something simple?" Am I missing something in this statement? You say you changed all these components so you can't use system restore? Try a system repair. How to do a system repair.--Boot from the xp cd and go past the recovery console to the install menu. Select repair the existing installation. You won't lose any data except the xp updates. Unless you have a slipstream sp1 Or SP2 cd you will have to d/l sp1 or sp2 and all subsequent updates. You MUST have at least SP1 installed and the updates for security reasons. Be sure the firewall and A/V is active before going online as you will be susceptible to sasser and msblaster. http://computervitals.com/

I disable system restore as it's a useless tool on windows.