Once you upgrade your router, check your cable modem if you are on cable. Mine was probably as old as my router. Exchanging it with my provider (free if you are renting it) tripled my download speed. While doing this I discovered adding a phone to my package dropped my monthly bill for cable and phone to $15 less than I was paying for cable alone and doubled my cable speed.

Also check the cable on anything connected to the router by cable, if it isn't Cat5 or higher replace it for another nice jump in throughput.