I think you will be ok there.The PS2 network adapter will be available in both USB/Ethernet formats,If you have a Ethernet Router i would go with the Ethernet option as this is slightly quicker than it's USB counterpart,also it's easier to setup..
If you like i can pass on the technical support telephone number(UK only) for the network adapter,they will be able to tell you right off what ISP's etc are supported..
Just drop me a PM and i will pass it on to you