Where To Begin Upgrades

I have an old laptop that I would like to begin upgrading. I'm assuming that I will need to replace most of the parts, but what should I focus on first to get better games running?

Specs: http://www.amazon.com/Dell-Vostro-1000-Widescreen-Dual-Core/dp/B001AMBAAG

Yeah, you wont be doing much upgrading on that.

No point upgrading that.

Time for a new laptop.

That's a bummer. Thanks for the advice.