Simple network: desktop, laptop, wifi DSL router

[marcus]

Are there any how-tos on creating a very simple network for 2 machines?
Google hasn't helped sofar.

I have a desktop, a laptop, and wifi DSL router/AP. The router has a LAN 
plug for the desktop. Can I use the wired port for the desktop, and 
wifi for the laptop? It should work, but I'm not sure how to set it up.

Like this:

- desktop wired to LAN port of router

- laptop connects to LAN and DSL with wifi (DSL connection already works 
with Knetworkmanager)

- both machines can share files on LAN


It should only require a few entries in /etc/network/interfaces , 
shouldn't it?

Thanks,

Marcus