My RSSI is constantly -50, so yours is fine, I guess the RSSI changes after how close you are to the router when you use the program.
Which firmware do you have on your dlink?
Are you using any wired connections? I have experienced reboots on my router, but it wasn't caused by the wireless network, and my reboots was not at regular intervals.
If I were you I would change/force my wirless channel to be on channel 6, to get further away from the 2 networks with channel 1.