unwanted interface keeps coming up

[ZA]

Hi I have a Knoppix 5 Hard drive installation. I have two NICs on my machine-eth0 is ethernet and eth1 is wireless. I don't have a wireless provider but Knoppix keeps picking and using eth1 by default. In order to use the network I have to keep runing the following command every few minutes

ifconfig eth1 down
ifconfig eth0 up
pump -i eth0

I tried to make these changes permanent by adding "ifdown eth1" to my /etc/network/interfaces file but the stubborn eth1 keeps coming up everytime. Is this because of some periodic dhcp client pinging? If it is then how do I stop it? The wireless NIC is inbuilt and I can't even remove it.

I am a newbe at this. Any help would be appreciated.
Thanks.

[sean.1986]

Can you not go to System -> Networking and then choose eth0 as the default interface to connect with?

[richard_earhart]

Are you able to shut-off the wireless interface in the BIOS? You SHOULD be able to do this and then Knoppix can't see the interface.