Help!!!!!!!!!!!!!!!!

Hi all
My computer recently got infected and i cant seem to find anything on the internet.
My Start bar is missing,my task manager has been "disabled by administrator" and my Registry has been "disabled by administrator"
I installed norton 360 as soon as i could but it didnyt help,now im left with a rogue computer.
Even if i restart my computer it comes to the same page
Please Help Guys

Try running the windows in safe mode (I think you press F8 before you see the windows xp logo is loading) after gettin into the safe mode just run the System Restore (well if theres start menu in safe mode).