For over clocking your better off getting an Intel e21xx series with a P35 mobo. The Asus P5K SE is $89.00. Tigerdirect has this one on sale.http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=3505668&CatId=2852
You could use your ram but you would need to buy a after market CPU cooler to overclock since it is an OEM chip.
This setup up would be like $190-$200 with shipping. The e2180 OCs to 3.33 on this board with the stock cooler. With the aftermarket cooler you could probably go higher.
Dont forget the thermal paste.