Two genres I'm searching for

Then I do, I do is perfect! It has an older woman (Kim Sun Ah) and a younger man (Lee Jang Woo)
It's more of a drama than a comedy, but It does have a lot of funny moments! In addition to the funny moments, there are a lot of heartwarming moments. I haven't finished it yet (I'm on the last two episodes) but people say that the ending is good. You won't regret watching it!

Aha I've seen both of those dramas :P

A japanese one (maybe not as funny as korean dramas) with Matsujun, for older woman younger man:
http://mydramalist.com/japanese-drama/15/natsu-no-koi-wa-nijiiro-ni-kagayaku

http://mydramalist.com/japanese-drama/23/kimi-wa-petto cute, funny Rom/Com with an older woman younger man plot also the movie version http://mydramalist.com/korean-movie/1691/youre-my-pet

A. Younger Male

Kimi Wa Petto (You're My Pet) http://mydramalist.com/japanese-drama/23/kimi-wa-petto

B. ROMCOM

My Girl http://mydramalist.com/korean-drama/48/my-girl
My Girlfriend is a Gumiho http://mydramalist.com/korean-drama/31/my-girlfriend-is-a-gumiho
Rooftop Prince http://mydramalist.com/korean-drama/3380/the-rooftop-prince