kareemhI Encounterd this problem with XP home edition and in the end I did a full re install
Then set the Auto re-boot check box to clear
Then each time I got a auto re boot I wrote down the details of the stop error e.g 000000,05x etc
Then Checked the erro log file in Control Panel Admin tools System righ click
and then when the info was on screen used copy to clip board option?
Then went to the Microsoft Support site and pasted it in to the search feature
Read the releavant article
Followed by updating in sequence any Windos Criticall updates reffered to
and by a process of updating etc
Identefied a problem with a Graphic Card
Replaced the Card and to date
No problems
according to Mcrosoft stop errors in Xp are often related to
hardware!!!
Roger