Network addressing

My SuSE desktop has an ip address of 192.168.1.4 and normally accesses the internet via a wireless router with a gateway address of 192.168.1.1 As this gateway link is somewhat unreliable I have an alternative gateway on 192.168.0.1 via a windows XP shared connection. The 192.168.1.1 gateway is ADSL and therefore my preferred route to the internet, but as it is unreliable is it possible to change the addressing on the desktop to use either the 192.168.1.1 or the 192.168.0.1 routes depending upon which one is available? If so how? Phil