Updating Video/Sound Card Drive
 

I know you have to figure out the brand of it then go to the site and update... but how do I do that?

Video/soundcard should be easy, just tell me what major brand it is (like ATI, nVidia, Creative, etc) and we'll go from there.
Most drivers made for videocards are in a bundle, meaning you could download the same driver package for a GeForce 4 Ti as a GeForce 7800GTX.

If your operating system hasn't identified it, then open up the machine, carefully inspect the thing, and you should be able to tell. If not, sometimes a bit of googling is required on old school hardware.

I mean how do I figure out what brand my video card and sound card is... after that I know how to upgrade it

I'm partial to using the left and or right eyeballs to read the lettering on the card. Punching any chip's model numbers into Google is a last resort if the thing isn't well labeled.

So there's no way to find this out without opening the computer

Go to Start Menu->Run and type "dxdiag" in the text box. Go to the Display tab and look at Name or Chip Type for manufacturer and model. Rise and repeat for Sound tab (except there's no chip name).

If your computer was pre-built:
Just install the drivers that came with the computer. Or at least see what kinds of drivers are on the CD.

If your computer was custom built:
Ask whoever built it? Look at the boxes the parts came in? Or hey, ask your mom and dad! I'll bet they know!