I have had 2 actiontec routers with no problems. there 54Mbps Wireless Access Point is very good.
Wireless networks have 2 standards at the moment 802.11g or 802.11b i would go for the G standard as it is newer and can be made more secure.
Above is a link to the router that i have, and found it very easy to set up.
You are right in saying that you will need a pc card for the other computer (known as a PCMCIA Card).
Dabs also do a card for this standard click here
and if you look this is also G standard.
G is also backwards compatible.
Its hard to explain but G standard devices can connect to B standard devices, but B standard cannot connect to G standard, as the G standard is newer and faster at 54mbs.
Hope this helps