sometimes that can be the worst thing to do if you suspect a virus or trogan.
I would play safe and download spysweeper and AVG and run both. They are both free . Just to be on the safe side in case you have picked up a trogan.
Everytime you reboot your PC reconfigures ,makes changes to the registry and the boot sector. If you have a virus it could make the situation 10x worse
Alternatively you could do a restore to the beginning of the week when everything was last ok .
Start, Control panel, System, system restore