I've got 7 of the named ones.
1 Seagal movie: Under Siege (that would make a great riff).
Don't seem to have any Van Damme movies on my shelves.
Under Seige would be awesome, but On Deadly Ground is one of my dream riffs. It's so amazingly bad, but you can't stop watching it.
Kickboxer is my dream JCVD movie to be riffed. I busted out laughing at it when I first saw it: really close to the end, he blocks a punch for the first time in the movie. I was like, "hey, might have been a good idea to start doing that before he kicked your ass and nearly blinded you."
Ladyhawke would be so good too. I actually recommend it unriffed, just to get a sense of how silly it is, but, with the exception of Matthew Broderick's misguided "comic relief" it kind of takes itself seriously as a movie. And, of course, there's the Allen Parsons Project "soundtrack" which is just the same 15 seconds of music played over and over.