Is your hair growing while your waiting for your animation to render? Try these tips. The use of layers is very important not only to organizing your work, but keeping it uncludered. I keep my lights on one layer, my character on another, and my particles and wind emptys on another along with boreing objects on another. This is important when rendering because when rendering only render the layer that you are interested in. For example if you want to check the fluid movement of your character, JUST render that layer. That way your 1982 PC doesnt have to take up a lot of CPU time rendering particles, grass, or objects that dont move. This will cut your rendering time dramaticaly. Also, look for the little pic render button all the way to the right of your interface and hit ctrl and this button. It will render your animation in the wire or solid format in about 1 frame a secound! After your satisfied with how your character moves then you can render all the layers together.This should save you years in waiting for test renders. No more painting the house while your waiting for your render to complete. Good Luck! Cindy.
Damn. There go my long coffee breaks. 
Good tips, cindy lou
(And don’t forget to use Alt+A to check the animation even before doing a render test. Ok maybe that one was obvious :p)