Do you want older or newer movies? And do you like comedic action or straight explosions and stuff blowing up? Here are some of my favorites, off the top of my head... I tend to like the funny or sci-fi type of action movies.

Die Hard 1 & 3
Lethal Weapon (all of them are good)
Terminator 1 & 2
Independence Day
The Rock
Men in Black 1 & 2
Robocop
Total Recall
Top Gun
Raiders of the Lost Ark

Btw, check out this list of "top 50 action films" from imdb.com... not sure I'd agree they're all action, but there are some great movies on here: http://www.imdb.com/chart/action