wireless internet question (help)

ok. I have a question.

I have a pole barn (which is really like a giant garage; it's two floors, has a bunch of stuff like a pool table, fridge, and heating. It's not like an animal barn like on a farm :P ) with a decent computer in it (runs windowsXP) but unfortunately cannot connect to the internet because we have wired DSL.

my question is, if I were to buy something like this:

http://www.amazon.com/Linksys-WRT54G-Wireless-G-Router/dp/B00007KDVI/ref=pd_bbs_1/103-3298464-0436610?ie=UTF8&s=electronics&qid=1188782781&sr=8-1

and plug it into my PC inside or in the pole barn, could I get internet in the barn? The barn is probably only100 feet or so from my house, is that too far? Does distance matter? All help is appreciated, OTers.

thanks for your help, I'm new to this wireless stuff.