DHCP with wireless and cable NICs in one computer

Hi,

I'm quite sure this is a FAQ, as it is quite common, that laptops can
access LAN both via Ethernet and WLAN. But my readings of howtos just
revealed the normal WLAN setup, but did not give me a clue how to setup
both access methods at the same time in a correct manner.

So, I have a LAN where router (192.168.2.1) and access point
(192.168.2.13) are different physical machines. To enable the WLAN
clients to also use the router, I chose the same subnet 192.168.2 for
everything. DHCP and DNS are setup on a third machine running Debian.

As I'm new to the whole WLAN story, I don't know how to handle laptops,
which can reach the net both via WLAN and ethernet. If I setup DHCP to
answer requests for both MACs, should they have separate DNS names? If
there is no special setup, which device will get the default route (in
case of a Linux or WinXP laptop)? Should I prevent, that both NICs are
on the same subnet at the same time? But how?

Can someone please give me either a pointer to some docs, which cover
this or just sketch a typical setup?

Maybe I should add, that all computers should offer samba shares, and I
would prefer, if those were available always with the same name to the
other users.

Thanks in advance for any help!

Ciao
Siegbert