I have contracted SAPE Malware that Norton cannot remove. Help?

I downloaded an Gameboy emulator earlier today and some weird ads immediately started popping up on Firefox and my firewall turned off, so I immediately ran a Norton scan and these three threats were detected:

SAPE.Yontoo.a3
SAPE.BrowseFox.17a
SAPE.BrowseFox.24e

Norton cannot fix them. What should I do?