Norton Internet Security 2010 hangs when doing a quick scan, please help ASAP

Hi Everyone Please help me out through this porblem.

 

Ok so here are the detials: When I go to scan now, quick scan, it scans till it checks for Hacktool.Unreal.A, on that exact moment it hangs the intire computer to a stage where I have to force my computer to turn off, by holding the power button on my CPU.

 

More details: I have norton internet security 2010, fully updated, (version: 17.0.0.136) Vista Home Premium 32 bit Service Pack 2 with all latest updates applied.

Other virus scanners whilst running Norton: MalwareBytes Anti Malware Pro, SpyBot Search and Destroy with Tea timer resident shield.

 

A few more details: Today i'm experiencing this problem, but I havn't before, even with these anti virus added. I have done a one click scan but no problems.