As long as you regularly touch a grounded/earthed metal surface while working inside your computer, so as to discharge static electricity, you'll generally be fine.

As for your motherboard, it supports up to 4GB of DDR-400 RAM (not DDR2 nor DDR3, so be careful what you purchase). It looks like it has 4 slots available.
This board is similar to the one you have, although yours is an OEM-specific board: GIGABYTE - Product - Motherboard - Specification - GA-8I915P-MF