anyone know how I can figure out what type of RAM I need (assuming there are multiple) and how I can figure out if I can put more into my computer (preferably without having to open the case first)?
Quickest way to figure that out would probably be
Crucial's system scanner. Run that and see what types are compatible. For example, for my system it says "Each memory slot can hold DDR2 PC2-5300,DDR2 PC2-6400 with a maximum of 1GB per slot"
It'll then try to advertise some memory. You can probably find a better deal on Newegg or elsewhere. Do remember that it's update recommendations do not take into account OS limitations (it's telling me to upgrade from 3 to 4 GB, useless on 32-bit XP).