D-Link or Linksys/Cisco is fine. If you need Static DHCP (DHCP reservation, where your computer or networked printer always get the same DHCP address) the new Linksys routers don't have that for some reason, D-Link does. If you don't know what Static DHCP is you probably don't need it.

Linksys have internal antennas, looks neater, cooler design.

To save money though, if you're not doing serious file sharing over wireless, or if your machines are not capable of wireless n protocol, there is no advantage to getting a wireless n capable router, they are more expensive. In order of the speed chain low to high you have b, g, and n. Wireless b is more than fast enough for internet. I don't think they even sell wireless b only anymore, they are all b/g or b/g/n.

If you do a lot of wired file sharing look for a gigabit ethernet option, but like the n option it's more expensive.

You can find these for probably around $30 US or so online.

Same here.