If we are talking live action, I liked Silent Hill and like the first two Resident Evil's for their cheesiness before they really went off the rails, which is saying something for an RE related product lol There was the previous Halo series thing, not Nightfall, but the one before about the boot camp. It's not particularly very Halo till the end, but I liked it as a story.
For something animated, Final Fantasy VII Advent Children, RE: Degeneration and Damnation I remember to be entertaining. Probably seen more, just don't remember at the moment.
Worst I've seen are probably the Super Mario and Doom movies, both of them for basically missing the point of what they needed to do lol