.NET3.5 / VS 2008

I've just recently started using C# (so I'm pretty much a complete beginner) and I want to try and make a very simple adventure type game, I would like some advice please on how to implement the following:

- I would like the user to be able to input their name to start with, so that they are the main character, and any reference in the story to the character is their name.

- then they have the choice of 2 options A or B

- each option brings a different outcome to progress the story in a different direction

- some validation so that the user can't enter anything but A or B and can type an exit command to exit the program at anytime

- a loop so the user can restart from the beginning once they've completed the game

- a stopwatch so that the user has a limited amount of time to answer

Any advice on how to do this, such as which Loop type etc to use would be much appreciated, thank you!