Dear,

I will found problem in winxp services are not running some time so how to solve it without format.

reply require for urgent.

Not are services run at any given time.
Here is a useful link for services.

Black Viper's Web Site

If that doesn't help you post back with which services you are having problems with, your OS (Home,Pro etc), service pack level installed and what is the problem. (what's not working, what is the symptom)