Hello, this is just quick fix for every Windows problem that is stubborn..
Put your Windows Installation CD and try to repair/reinstall Windows.
If you cannot do this, than you are going to have to restart your computer.
And when your computer restarts, enter the bios. Set CD to boot before the hdd.
Press button to save and exit bios/cmos. The computer will restart, and it should prompt you "Boot From CD". y .... I would say, just completely reinstall windows.
VERY IMPORTANT... As soon as you finish installing windows, run NAV(if you do new install you may have to reinstall....)
Do the most thorough scan of all your harddrives(My Computer)
Do this until no viruses are detected on you files. The reason is, the symptoms you described sound like a master boot record(don't worry what that is) virus I once had. It is very pernicious and self-replicating.
If nothing else, just replace your hdd, since you say it is new computer.
NOTE: Programs like those free ad-blockers and spyware-removers can cause more problems for your computer than solve. My advice, remove all that b$. And just use your norton. And I think there is another norton product for blockups and other things geared towards protecting you online. Setup a firewall, disable cookies or just make em delete themselves after every session. Make sure your antivirus program is set to autodetect enabled.
Good Luck... Best I can think of