I would just replace the whole system with a newer used setup. For not much more than the price of a motherboard you can get a system with 3 times the speed.
First few gens of i3 and i5 you should be able to find for under $100. Buying a new motherboard, doing all the work of re-installing Windows on it, swapping components, etc... or spend a tiny bit more and get a new system.
If you really just want to replace the motherboard, look for the same model you have now, would be simplest to replace, no need to mess with drivers or system not booting.