gotta be A Gentlemans Dignity
Chief Kim and The Lover. 
For movies- definitely Twenty.
Every Kim Seulgi drama. (Oh My Ghostess, Queen of The Ring, Surplus Princess, Splash Spladh Love.. Etc!)
The Sound of Your Heart
Potato Star
Marriage, Not Dating
Emergency Couple
Ex-Girlfriend Club
Falling for Innocence
Lie to Me
Modern Farmer
She Was Pretty
A Gentleman's Dignity :)). Incarnation of Money was hilarious too even though it's a serious drama.
For me...

Jealousy Incarnate
Shopping King Louis
- A Gentleman's Dignity (the prologues are the funniest)
- Come Back Mister (just watch to see for yourself)
- It's Okay, That's Love (kwang soo)
- Heal Me Kill Me (ever episode honestly)
Marriage not dating 
weightlifting fairy Kim bok joo 
she was pretty 
Definitely season 1 of After School: Lucky or Not
Recommend it!!
Shopping King Louis 
Marriage not Dating
Reply 1988 and Kill Me Heal Me
The Sound of Your Heart
Modern Farmer
Reply 1997 were the funniest I've watched 
Recently, Chief Kim! :D

Edit*

Gentleman's Dignity is funny too, especially with the 4 friends. However, it does get frustrating and annoying at times lol
Personal taste
Please, come back mister
Coffee Prince 
My name is Kim Sam Soon
History of a salaryman