Continue of my wireless upgrade

So in my last thread I got some good info. Now I have a new idea. Or two. I've got a router in one building and it runs a wire to another building with a old 10/100 switch. I was wondering if I could replace this switch with another router so the two routers are connected via cable but only one has internet. And both give a wireless connection. Would this work? Or would I have to get a router that supports the "up-link" thing like the 10/100 switch does?
Or I could get an AP and plug that into the 10/100 switch gaining another wireless connection with the range I want throughout the property.

I was looking at a couple of routers and AP's.
What do you think, and would they work how I want them too?

Routers:
TP-Link TL-WR541G -- reasonable price
or D-LINK DIR-635 -- pricey, but has N thinga which would match my laptops network.

APs:
Netgear WPN802 -- expensive
Netcomm Super-G NB600W -- very cheap


And do you think, if another router would work wired into the existing one, that just a cheap router with an antenna and 1w amplifier would be a good option? Would it give the most range?

EDIT: Another thing.. Would a 12dB antenna like this one 12dBi Wireless Omni Antenna 2-3Km Range DLink Netgear - eBay Antennas, Repeaters, Extenders, Wireless Networking, Networking, IT, Telecoms, Computers. (end time 11-Feb-08 19:24:22 AEDST) give a good 50m through a wall range and decent signal and speed?

Thanks.