XP slowness

I have a new Toshiba Satillite Pro 6100. (laptop) I have Windows XP on it. On bootup, it becomes painfully slow…as in taking 2 hours to even boot to the Desktop. It seems that the initial boot does fine, but when it actually begins to boot to Windows, it gets painfully slow.
Only problem is that this is the second one of these machines that has crapped out like this.
I changed the HDD on both and installed XP on the new HDD. But 2 machines in one month has me suspicious. Has anyone else had this problem?
Any ideas?
Thanks!