Can anyone help solve disappearing wireless network

HI,

I am having an annoying problem with my router, I'm hoping someone can help me with it.

I just got the D-Link WBR-2310 Rangebooster, I set it up and it worked fine. Now every so often, could be once a day, sometimes every few hours, the signal suddenly disappears and I get disconnected. When I look at the list of availables networks (wireless) I don't even see it listed (and I'm standing right beside it)...

The actual router seems to be functioning, all lights are lit etc... When I reboot it, it will work fine again.

The computer that is connected with an ethernet cable off of the router works fine even when the wireless connections aren't working. I did notice however now that I'm having this problem that I see on the taskbar "Aquiring Network Address" (in the comp that is wired to the router... while I have problems)

Originally I thought it was because I was trying to use a Mac system and perhaps it wasn't compatible, but now another PC running on wireless also doesn't see anything.

Here are the wireless settings I'm using:
Auto channel scan is enabled
Super G without Turbo
Extend range mode enabled
Web basic enabled
Authentication Open
64bit
HEX
WEP Key 1

Any help greatly appreciated...