Can't run any program on windows 7?

I downloaded BSR recorder and suddenly I couldn't open anything. I restarted it and i have no icons. If i run anything it says there isn't a program to run .exe programs you need to install something. if i run computer it says "the parameter is incorrect". Im writing this on another computer. I've already tried to system restore but i cannot open it. please help me, im almost positive it isn't a virus