Problem with my Default Gateway

Hi All

I have a network connected with 500 systems having network configuration of 192.168.0.1-192.168.1.255(subnet:255.255.254.0)and with the default gateway of 192.168.0.2 . The systems with IP range 192.168.0.0-192.168.0.255 can able to access internet where as the systems with ip range 192.168.1.0-192.168.1.255 are not able access internet.can any body help me in this regard