Here's what I would try doing.
1. Getting rid of norton because it uses probably as much resources as a trojan
2. Go with a better product (AVG, Avast!, Avira...)
3. boot into safe mode and try to scan and quarantine or delete that way. I usually delete and have no trouble but sometimes I quarantine so it can't run on my PC again.
IMO, Norton is awful at working with viruses, if you can I'd go with another scanner or if you don't want to, go and use the Trend Micro Housecall online scanner which is free and works well. You can find it here: http://housecall.trendmicro.com/
You could also try using a program with a rootkit scanner such as bitdefender and see if that finds anything if all else fails.