Should I upgrade my ram?

[Viper87227]

I curreny have a gig of low quality ram (CAS 2.5 PC2700) and I want to get into overclocking, so I assume getting something also the lines of HyperX or XMS is what I need, but being a noob to the hardware scene, I have no idea what most of the stats are. I see all kinds of different timings, 2-2-2, 2-3-2-5, 2-2-2-3-1T, ect... What does all the different latiencies mean? If I decided not to overclock, how much would simply having generic cas2.5 ram vs. good low latecny ram matter, would I see performance gains? How about if I went from 1gb of the decent stuff to 512MB of the good stuff, and did overclock, would that give me greater performance over just have the 1GB. BTw, my CPU is a 2500+, stock speeds, and if I decide to get into overclocking, ill upgrade my mobo to a NF7-S