Yes, it is worth upgrading to at least 1Gb of RAM but since I am familiar with the prices on newegg the difference between prices of 512Mb and 1Gb
is so small I would buy another 1Gb of memory for the remaining slot. Try to
buy the same latency memory. Actually you probably can find 2x1Gb for
little bit over $25 and then not worry about latency and position of memory modules.
If you decide to buy 2x1Gb and you can sell on Craigslist 512Mb memory which you will pull out of laptop. You may be able even to get the present to your brother for Eastern Orthodox Christmas (7. of January) from the
money you make of Craigslist