make sure that you are using the latest firmware on the router.. and try a power cycle of the router.. some types that will make a huge difference!! What type of router is it?
BTW you should get about 75-80% of your ethernet speed on your wifi connection..
I am about 19,000kbps and i get about 15-16k on my 54g connection.. If you are still using an 802.11b, 11mbps, then it would make sense that on the wifi you are only getting about 2000ish. most of the throughput on those ranges between 2.5mpbs and 5.5mbps.. which is less than the overall bandwidth of your connection.