Best Practice for moving web server

[Anddmx]

Web Server is being moved to new office just build.

I really need this to run smooth and I need some info from the experts

The office has a T1 line and I need to know which is the best practice to set this web server back up and online with little down time.

Iam no expert so I have to ask please dont flame me lol

1. what is the best router to work with on T1. I usally work with a cable modem with cheap router and effective for small enviroment.

2. I hear alot about DMZ, is DMZ just a switch on the out of the router? I want this to be secure

thanks