I have reviewed you system requirements and specifications.
I recommend going with an inexpensive DDR2 memory module. One the least expensive, that will definitely satisfy your processing needs, would be the 1GB PC-5300 DDR2 Memory Module offered by MicroCenter.com at a low cost of $29.99 (US dollars).
Here's a link to their page: http://microcenter.com/single_produc...uct_id=0273822
This memory is intended for those on a budget, runs on low voltage (1.8 Volts, reducing power consumption), and is non-ECC.
$30 for a Gig of RAM is a excellent price, and the hardware is moderate in quality.