My computer is very slow when scrolling down on programs like Microsoft Word. Should I add more RAM, vid. card?

The easiest way is to upgrade the RAM. If you get 512mb more RAM you will notice a dramatic difference in speed. Make sure you use the same type of RAM though. I would think your type of RAM is DDR. I may not be right so i would advise you to ask a professional. If you install the wrong type of RAM your computer will be broken.