Either its a poor installation at factory for Vista so re-install would be a good idea, do a clean install through, no ghost images as you will back up the problem too.

Or there's a conflict within the "services" in the MSCONFIG command, you could try disabling all services on the services tab in the system config utility and the startup tab then restart and see, make sure you tick "hide all microsoft services" check box before selecting disable all in the services tab. Good luck