Vista : System event notification

Hallo

I deleted data on 2 reg keys that said "nuke on delete" and when I rebooted I got a temporary desktop and my documents and program files had dissappeared, although I can find them under my user name on C: drive. I created a new account and A message popped up "Windows could not connect system event notification" My internet connection is now broken, and when I tried to restart DHCP I am told the RPC service is unavailable. When I tried to restart RCP I got error 1079. The account specified for this service is different from the account specified for other services running in the same process. Is there a way I can fix the internet connection and get my desktop, documents and programs back? My restore points also vanished and am unable to create new ones.