Did SIW not give you the model of your motherboard? It should have been under the Hardware/motherboard. Well never mind about it for now, The report was useful in a different way. We now know what memory you currently have installed. You may be able to install some newer, faster memory but your system will default the speed to the slowest installed chip.
I.e you currently have RAM at 200Mhz, If you were to install 400Mhz capable RAM then the motherboard would only run it at 200Mhz.
Your current intalled memory should be 2x sticks of DDR 400 (PC3200) 512Mb RAM
Now you can still buy DDR 400 (PC3200) RAM and fairly cheaply as well so don't go wasting money on faster RAM if you don't intend on removing the old sticks already installed. I don't think that you would receive much benefit from using faster RAM and I have lost those specifications so I'll need a minute to work out what memory can be taken by the motherboard.
If you provide what county are you currently residing in then we may be able to give you some recommendations.