That is a system error not an error produced by the emulator. It would seem that kernel32.dll a critical system file which virtually every application on your system runs through has been damaged somehow presumably when removing Norton IS from your system.
The only way I can think of fixing this is backing up all the critial data you have, then formatting and reinstalling the OS though if only no$gba returns this error that may be too much trouble for the moment. If not tech-savvy then I suggest taking your system to the local PC place and let them handle the backing up formatting and reinstalling of your OS though this could be quite costly so as I said if only no$gba does not want to run then you may have to cut your losses and just moved on without it.
I say again though this is a system fault (specifically a damaged/corrupted windows installation) and not related to or caused by the emulator.