Some aren't classics but I like the following:
Ong-bak: Muay Thai Warrior - good action and great fighting scenes
The Punisher - the main character actually got into really good shape for the movie,plus there are a bunch of guns and killing
Bruce Lee movies - just in general good action
Rocky movies - yo adrian!!!
Predator, predator vs. alien, predator II - just gory killing
End of days - I just like it
Try punisher though. Makes me want to go out and shoot some bad guys everytime I watch it.