RAM is the best performance-booster you can add to your computer. This will be a factor of the VRAM in your system. In most cases you'll need at least 2-4 megs of VRAM for millions of colors on a larger monitor. I have never regretted the day I splurged on a 17-inch monitor at 1024 x 768 pixels in millions of colors. You're even luckier is your area has affordable access to ISDN lines or cable modems.
Access just keeps getting better and better.
If you're getting a new machine, get at least 6 gigabytes for your hard disk. The latest browser downloads are about 12 megabytes. Sound capabilities, stereo speakers. Mine are built in to the monitor, which is great if you don't have a lot of desk space. Also nice is a separate telephone line so your phone won't be busy every time you're online.