I think I should stay in the airport. I thought about getting a room for the day but considering this time of the year (flight will probably be delayed) I think I would waste most of my time waiting (shuttle busses, security check).

I just want a kind of quiet room with a place to seat comfortably and a plug to charge my electronic stuff.

I guess I should rather spend the time in a United Club (terminal A vs. C) rather than in a restaurant in terminal C.