Help with Vista resetting personal preferences on each system rest

I have an HP with Vista Home Premium installed with SP1. It automatically

downloads updates. I am the only user & person with access and there is only

my account on the computer under my name so it show to be the sole

administrator.

Every time the system restarts or reboots my preferences are lost (including

system self reboots when updates are applied). The Start Menu reverts from

Classic which I prefer, to the default. Personal preferences for installed

progams like games are removed so I continually get a pop up to accept them

each time I want to play them, even though I go through the routine of adding

them as accepted.

I need some help as to determine what is causing this and how to fix the

problem.