Shatner cheesy? I think not.
Seriously, he has his moments. He also has moments of brilliance. The scene in Star Trek III where he finds out David is dead and stumbles back and falls in front of his command chair is just brilliant. I don't think he's ever done a better job of conveying emotion than he did in that scene. (meanwhile, "KHAAAAAANNNNNNNNNNNN" is just plain cheesy.
) Plus, he's friggin' hilarious in
Airplane II: The Sequel.
I like cheesiness in films. Without it, you'd just have documentaries and boring dramas. Cheesiness = fun.
Now, corniness is another matter, I can take or leave it.