XP keeps "resetting" itself

[x3cuti0n3r]

hello.
I've been experiencing this strange problem with my pc. Almost everytime i start my pc, xp "resets" itself as if its a fresh copy of windows....the background is set to "bliss" (the default one) ..all desktop icons and settings are gone... the xp silver theme is changed to blue again...and it even asks me to take a tour of windows xp which usually pops up upon fresh installation of windows. moreover the worst thing is that every program goes blank as if its freshly installed too... firefox loses it's bookmarks and asks me to "import bookmarks from IE" (a prompt *again* displayed at fresh installation). Azureus (torrent downloader) lost all the torrents i've added and every option is set to default. i customized taskbar and start menu... (added quick launch etc) ... switched to default... and messenger doesn't remember my ids... every program is as if its newly installed.. this problem has been bugging me for months... i doubt its anythin related to ram or hd cuz i recently added a new hd and ram and a power supply as well... computer specs are:

D865GVHZ (recently changed under warranty)
P4 2.8 Ghz (recently changed under warranty)
1.23 GB Ram, 120 GB HD,
running windows xp professional..

Any help would be appreciated...
Thanks in advance....

[Sole]

Sounds like something with user accounts. If i am right about this, windows asks you to enter a name the first time it starts up and then makes that the administrator account, I have never tried entering nothing there, so I don't know what would happen, do you leave it blank when it starts up or enter a bunch of names down the list?

If its not that then my guess would be a faulty windows install, is this a copy of windows you downloaded somewhere? If not, then try formatting your drive and reinstalling windows again. If its a virus or something causing it then that should get rid of that too, if it still does the same thing that probably means you have a buggy windows CD, phone microsoft and try to get them to replace it (do they even do that?).

[x3cuti0n3r]

There's only one windows user by my name and it doesn't even have a password... windows doesn't show user accounts screen upon logon as there's only one sole user account...logs into my user directly...and the administrator account is displayed in the safe mode (of course)... i recently formatted c drive and flushed my windows... no use... computer is even booting slow.. even before the "windows xp" screen loads... i didn't download this copy of windows... i dun think it's any software/virus problem else i'd have chalked it out either thru task manager or my antivirus wud have detected it...think it's related to hardware... anyone havin any clue dat it cud be my hard disk? I purchased it around 6 months ago...it developed some bad sectors and i had them repaired from the company itself (i.e. seagate) ..scandisk doesn't show bad sectors now though.. there's sometimes this sound from my CPU as if something turns on and then off.. i am 100 percent sure it's not the fan (neither of heat sink nor of power supply) and nor is it my dvd drive... i have a doubt it's coming from my hd... whenever the sound comes, the LED of "loading/busy CPU" lights up and my desktop+taskbar freezes for a few seconds as if it's loading a heavy application... when there's no application running at all in the taskmgr and no processes takin up any amount of CPU instead of the default "System idle process"... i am not pretty sure though... help needed....!