How do I get rid of a Hacktool virus (High Risk) with Norton Internet Security?

Before you answer, I want everyone to know what I'velready done. I already turned my system restore to off mode, I installed the virus definitions, and ran a full virus scan in normal and safe mode. After that, Norton Internet Security still couldn't remove the Hacktool virus. I'm a little apprehensive about trying to install more antivus programs that may a negetively effect the Norton Internet Security. So if you have had this problem and know how to truly and successfully remove it, any simple explanations will be great. I'm not really computer savy. My hubby unfortunately had to leave for a mission with the military and he usally fixes these sor of problems, Thank you for your help.