Lots of lag from WRT54GL or Zoom X3 modem?

[Scythe]

Hi, I'm a gamer and im experiencing lots of lag and high pings with something on my network. I need to get this fixed.
I'm running 1 pc (192.168.1.104) connected to Linksys WRT54GL (192.168.1.1) via Wired in Port 1. From WRT54GL it connects to a Zoom X3 modem (10.0.0.2). I believe it is the modem as tracert www.google.co.uk reports 150-250ms to connect to the modem.
I tried changing the modem to the same ip range as the router (192.168.1.*) but then I cant seem to connect to the modem or to the internet.

Any ideas?

 

[BenST]

Can you post an image of your tracert window?

 

[Scythe]

Can you post an image of your tracert window?

How strange, the modem has a ping of 16ms? I will see if it rises again and post it.