I'm wanting to get more room on my computer, which harddrive should I go with, The Western digital 7200, 40 GB, or the Seagate Barracuda. Also I'm not sure what my old hard drive is, (my computer is a HP, 8566C, Pen 3 500 MHZ, upgraded to 384 ram, it now has a 17.5 GB harddrive) and if it is a...