Page centering on screen

[Johkaz]

Hello,

I am wondering if anyone can help me with my website please?

http://johkaz.byethost10.com/

I have had some help with making it, but i can't find out out how to get the screen and page centred. I used Frontpage 2002 to assemble it, so i have a very limited knowledge of the actual coding that it contains. My screen on my computer is set at 1152 x 864, and i want to get it centred to that, and if possible screen resolutions below it.
If it needs the coding changing, can some please explain it to me in laymans terms.

Many thanks in advance.

Gary