Spaceballs is one of Brooks' worst but I wouldn't call it terrible. I find it perfectly watchable, and with a few really cool ideas and gags. Overall it seems to be his least deliberate film, with jokes drifting in and drifting out with no real rhyme or reason. "We've been jammed" is still great though.
It's still leagues above that animated cash cow of a show G4 slapped together to make a quick buck.