hitman pro 3

hi, i recently had a spyware problem where i had virus alert next to the clock in the task bar, i eventually managed to sort the problem out using hitman pro 3 but as this was a free download from an unknown source, {sounds stupid trusting something like this as this was probably how i got the spyware in the first place}. i was just wondering if this is a trusted and recognised program for this sort of spyware removal and are there any other programs i can run to give my pc a good health check. my norton antivirus package seems to be running normally and i can now use microsoft updates , both of which were disabled by the spyware