Linksys Wireless Router :: Cisco WRT120N Keeps Disconnecting

My Cisco Linksys WRT120N router keeps disconnecting, my family and me are all using the wireless connection. But sometimes the router just disconnect us all, its like its restarting, it only close down for like 5 - 10 secounds and then its back on. Sometimes it does it like every secound hour and sometimes it does it 3 times in 10 min. I usually play games on it and even tho I am the only one using it, it still disconnects. We got 2 wireless cameras running on a secound router that is merged (Thats what the nerd that setted it up for us told me) with the primary existing router. I am not really that good at computer I just dont want to get disconnected all the time.