Computer advice needed-memory upgrade

All memory manufacturers follow the same set of specifications to make memory chips. As long as you know what type of memory is compatible with your motherboard, you are free to choose whatever brand you like.

I just did a search and looks like your computer can use PC2700 DDR CL2.5. You should be able get 1GB for around $100-$120 (without coupons and deals).

I don't know if you're planning to install it yourself or let someone do it. There are several things you should know before installing to optimize the performance of the memory.
 
All memory manufacturers follow the same set of specifications to make memory chips. As long as you know what type of memory is compatible with your motherboard, you are free to choose whatever brand you like.

Yes, and no. True, there is a set minimum standard, but the big players like Crucial, Kingston, etc, go above that with higher tolerances and levels. That being said, unless you're hardcore overclocker, power user or gamer, I doubt you'd see a performance difference between Crucial and a generic maker.