category order and subcategories

I have just started with WP and am slowly building my pages. I have now come across two questions relating to categories that I cannot find an answer for.

1. Can I change the order in which the categories are displayed? They seem to be alphanumerical in order but I would like a different order.

2. I have created a number of pages with subpages and the links are displayed nicely in an indented list. Can the same be done for categories and subcategories?