WordPress MU

I would like to change all of my categories to pages, how can this be done in the simplest of ways?

I am using wordpress mu 2.8.4

Depends on what you mean.

Do you want a link in a nav bar to a page that shows category archives?

or do you want the content of Category X to all be on one Page? As in a WordPress Page.

both ways if possible, also i would like to place categories as sub pages on nav bar?

Thanks!

Take a look at http://pixopoint.com/products/multi-level-navigation/
There are heaps of otions for creating custom drop-downs

Regarding pages,
You might need to create a page template with the list categories php function where you need it.

"i would like to place categories as sub pages on nav bar"

Look in your theme to see how the pages nav bar is made. Make a duplicate but pout the category tag in there instead.

I really don;t think you mean you want category content in an actual Page, because Pages are outside post heirarchy.

I'm pretty sure you mean a single page (note the small p) and that'd be a category archive page.