Love At First Bite (1979)
Young Frankenstein (1977)
The Monster Squad

I actually thought the first Evil Dead had a lot of dark humour to it like that tree with sexual intentions. I find humour in a lot of horror but especially these:

Street Trash
Cast A Deadly Spell
Witch Hunt
Brain Damage
Frankenhooker
Basket Case
Bad Biology
Society
Creepshow 1 and 2
The Monster Club
Night Of The Creeps
Night Of The Comet
City Of The Living Dead
The New York Ripper