I chose some dramas from my PTW list but im not sure which one i should start first.I hope you can help me.I want something fast-paced and keep me interested through the whole show.These are the options;

N no Tame Ni

Punch

Kazoku Game

Cruel City

Angry Mom

I recommend Angry Mom 100%.
It might not be the typical romance comedy drama because it focus on a lot of different subjects and that's why it's unique and awesome. You will be hooked.
Angry Mom.
Like Neylana said,  don't expect a comedy. The drama talks about some serious issues so there's not always room for laughter (but Han Gong Joo and her minions are absolutely hilarious). Nontheless, it's a really enjoyable drama and Jo Kang Ja/Bang Wool is really the best character/mom ever! 
grades from me
angry mom 9/10
punch 10/10

I haven't seen the others.
For fast paced I would say Cruel City (the description is a bit misleading since there is a lot going on and the whole revenge thing doesn't even start till much later ), there are twists and turns almost every episode. Punch is more battle of nerves  between the characters, starts slow-ish but picks  up. N no Tameni is slow and psychological, you get a bit of the puzzle each episode. Kazoku is your typical psychological Japanese drama. Angry Mom even while dealing with murder and school bulling is the most lighthearted out of them.