Super Nintendo Entertainment System ROMS - safe? ?

I really care about my laptop ever since it got fixed; my anti-virus is only Norton from 2005 (horrible, I know, PS does anyone know any good spyware / virus scanners? My sister got a free edition of AVG, but can anyone confirm its use?) Anyway, I wanted to try and play some SNES Roms (mainly just Super Mario World), and I read about the ROMS and emulators, but I'm extremely wary of downloading *any* .exe programs, even with a Restore Point to back things up, because sometimes System Restores don't get rid of the problems. Are these rom things safe?