Click on Compatible Products on the left. You have to double check that your BIOS supports these processors, that would have been up to Dell to release.
Put your service tag in their support system and check th BIOS download, see if they say what CPUs were supported/added by revision. Good luck.
hi angie_29
Its a bit of an oldish computer (from ~2007) if you want to upgrade the cpu you will need a new motherboard to support a newer cpu.
Most likely you will also need to upgrade the ram and the psu. My advice would be to save up for a new computer instead, as the graphics card in the vostro 200 is going to have a hard time running todays games etc.
EDIT: scottie is right of course my post was made from the point of view that it doesn't make much sense (to me) to put money into an old system. But yeah it should be possible to upgrade the cpu