Wireless Routers

Has anyone had any experience with them?
See, fing is, my mother decided we are going to re-paint the house and stuff and she said if we could buy and install a wireless router as opposed to having wires all over the house. The house has 2 floors, my comp is in the upper floor, the other is on the lower floor. I have a DSL connection. So I was thinking of buying a router and two wireless NICs.
I know how to set up routers and stuff, but I haven’t had any experience with wireless ones. The things I’m most concerned with is low latency and good reliability. Since I play Guild Wars and Battlefield 2 a lot, having a low ping is a must. Does having a wireless router somehow impede that? How about reliability? Is it OK? And does throughput, i.e. download speed compare to that of a wired connection? I was thinking a TP-Link TL-WR642G 108Mbps router.
Thanks.