Windows XP Freezes on startup after installing Service Pack 2 :o(

Hi,

I have a Dell Inspiron 5150 Laptop. Recently i had to re-install the OS (Windows XP Home) due to the pc completely freezing & dell techs advised to completely re-install.

This done from the CD (XP Home with SP1a), all went well... UNTIL ..... i installed SP2. I did all the hotfixes & other updates that windows update listed, as well as other pre SP2 updates.

Once SP2 was downloaded & installed, i restarted my laptop. Sadly once again it froze at the XP logo screen (

I have another OS CD that has SP2 already installed that came with my laptop, but once I ran this CD to reinstall windows it froze half way through the installation (stopped half way through installing devices) , so had to do a complete reinstall with the OS CD that only has SP1a, which went on fine.

When i either uninstall SP2 or simply do a system restore to pre SP2, it works fine! I have had a new Hard drive installed today just incase, but alas same problem occurrs.

Any idea what the problem could be or how i can 'fix' it? PC is running ok without SP2 but obviously somethings amiss & I cannot download alot of upgrades (IE8, Windows Live Messenger or anything else that is only for SP2 updated systems)

Thanks