Martin - Suspicious Minds.
The 3rd act (Martin and his "dog") are hilarious. The others tried so hard not to laugh.
Golden Girls -
The Case Of The Libertine Belle. The "Murder Mystery" episode. I crack up every time Dorothy demonstrates slitting a throat.
King Of Queens -
Pole Dancing Episode. Doug convinces Carrie to take a pole dancing class at the gym, but she ends up being terrible. Hearing how her father is affected and watching Doug pole dance = hilarious.
Law and Order: SVU -
911 Episode. Olivia tries to find an abused young girl who is speaking on a dying cell phone that can't be traced. Amazing.
This is all I can think of right now lol