Your code would look much nicer if you put each statement and each } on its own line.
To make a nice responsive menu, you should not use delay(). The first delay() in your loop() means that you have to hold a button for up to half a second for it to register. There is a sticky stickies in the Programming forum on using millis() for timing.
One thing thats missing in your approach is to get from page 1 back to page 0.
You're not explaining what your trouble is. Can you describe the difference between observed behavior and desired behavior?