Wlan design: access point vs. wlan interface

Hi all,

please apologize, half of this message may be off topic.

I'm building a home network using a standard DSL modem/router (Netgear
dg834g). This works fine for all computers equipped with a wlan card.

I'd like to include a file server into this network, it's an old
machine running debian and equipped with a standard LAN interface. For
practical reasons I can't connect it to the router with a cable, so I'm
thinking about how to include it into the network.

The most logical solution would be to equip the machine with an
wireless interface, but that's quite a time consuming task as i would
have to find a supported wlan chipset, patch the kernel etc.

I do possess another wireless router (netgear mr814) designed to work
combined with a dsl modem.
I'd like to know whether one can use this router as a simple wireless
access point, and have it be part of the original network (sth. that
doesn't work out of the box as the thing is designed to be a router).

Could anyone give me a hint whether this is possible, or do I have to
connect the server via its own wlan eth device. In that case could
anyone reccommend a chipset that works fine on a debian sarge minimal
instsallation.

Regards
Matthias