Vista+XP+Wired+Wireless

Hello,
I have three computers (2 vista, 1 XP) that I want to hardwire via a
HUB/switch. I then want to connect the hub to the internet via two of the
computers that have wireless internet (1 vista, 1 XP). I havn't begun to
connect the hub together, and I may run into problems. I have a few questions
about this process and thought I'd come here.

1) Has anyone setup a system like this and, if so, what are some
recommendations?

2) If a computer is accessing the internet, will it automatically use all
the resources available to do so? That is, will the computer access the
internet through both wireless connections at the same time? If this is not
automatic, is it possible to configure this to happen?
--
Thank you,

excelBRISKbaby