One of my favorite marriages of genres has been the Horror Comedy since I first saw Monster Squad as a kid. There are too many to for a comprehensive list but here are my Top 5 (since 2000)
5. Dead Snow (2009)
Norwegian Nazi-Zombie film, Dead Snow is one of my favorite zombie movies in general and while it is a somewhat less directly comedic piece than the rest, I felt it definitely earned its spot on this Top 5 list. It follows a fairly standard "group of male and female college friends on vacation in an isolated cabin are beset by evil" premise but shines in its use of humor alonside copius blood and gore. A sequel is coming out soon called Dead Snow: Red vs Dead and I personally cannot wait to see where it goes.
Here is a trailer with subs which is the way I recommend seeing the movie . Something about the dubbed version didn't do it for me but to each their own.
4. John Dies at the End (2012)
Based on David Wong's first novel of the same title and directed by Don Coscarelli who also did Beastmaster and Phantasm this flick had me sold when I first heard about it and for once I was not dissapointed. Quick, witty joke pacing and utterly strange characters and situations set this firmly in the 4 spot. Maybe less gore than some of the others on this list but it makes up for it in pure creepy weirdness.
Also I highly recommend reading the book and it's sequel This Book is Full of Spiders: Seriously Dude Don't Touch It.
3. Zombieland (2009)
If you haven't seen this movie then there is a strong chance we can't be friends. Coming in at third just a hairs width from a three way tie with numbers 2 and 1. It was a painstaking enough decision to rank all three so no need to tell me how stupid I am for ranking it here. It is a fantastic movie and I love every minute of it so seriously if you haven't seen this you really need to.
2. Tucker & Dale vs. Evil (2010)
This is a breath of fresh air in the genre with a unique twist on the killer hillbilly and hapless coeds story. Tyler Labine and Alan Tudyk as the titular Tucker & Dale are best friend rednecks who just want to fix up their new vacation home when they are beset by insanely judgemental college kids and through a set of misunderstandings, mishaps, and skinny dipping... hilarity and violence ensue. A sequel is also in the works or this one.
1. Shaun Of The Dead (2004)
You got red on you...
No seriously this time if you haven't seen this yet we can't really be friends. Not only a hilarious and strong zombie flick, Simon Pegg and Edgar Wright's first film in their Cornetto Trilogy is the greatest tribute to the zombie subgenre created by George A. Romero I have seen so far. With in jokes, blood and easter eggs galore this is definitely the number 1 in my top 5 Horror Comedies.