i think you need to state your questions a bit clearer.
By a new screen, do you mean a fake windows interface?
How detailed are you planning on making it? multiple windows? resizing windows?
it might be easier to make a dos/linux prompt, like in enter the matrix, especially if the game is about hacking.
when you ask questions, just remember that whoever is trying to answer them knows absolutely nothing about what you're trying to do.
the answer to "Confusing Title i know but how would i go about making a new screen while running my program could be running" this snippet:
it makes a new screen.