Here is the information about your current processor:
*Socket AM2 AMD Athlon 2850e 1800MHz 22W G2 ADJ2850IAA4DP
There are some things you might need to consider before making the purchase, and not only the processor type. We see that this single core cpu consumes 22 watts of juice. That means that you could have a limitation/problem when it comes to the power source after upgrading. There are some good and cheap dual core AM2 processors; but this upgrade could cause you a problem because of the dual core wattage which range from ~50 to ~125 and maybe more after load. Maybe it is possible to upgrade, but I would suggest you pay close attention to your power supply as well.