Hello all

I have just started to learn Dreamweaver and have a problem.After creating a few pages i have noticed that my left navigation bar seems to move up and down when i click on the different links on that nav bar.It also moves out of place when i add new content to a page,how do i make the navigation bar stay still regardless of what content i put on that page?..do i have to merge and stretch the cells so far down the page or is it something to do with the % and pixel size of the table?.Sorry for asking such a newbie question but its becoming frustrating and i cant seem to resolve it:(