Stillhouse

It is part of the North Terminal (Check-in and ticketing, as well as bag claim) Flights depart and arrive from Councourse C, and the international Councourses E,F for International flights

I have just done this coming from the UK (last week ) - I spent 6 months worrying that I would not have enough time with 2.25hrs after reading comments on websites. Don't worry I went from the Gate in F terminal to the Gate in C terminal via the plane train - through immigration, customs and security in 1 hour.

At the terminal 2

Everything but delta is North

Delta check-in is located on the Domestic South Terminal!

To cool water for the refrigeration system

Is really hard to say without knowing which airlines she is flying from. But all airlines should have that info on their website.

At least 1 and 1/2 hours. They board 20 minutes before scheduled time

North terminal

Train goes to every Concourse which is every terminal so yes. T-D and partially E are domestic and Some of E and F are international