Does my computers need to be wireless

Hello,
I have two desktop computers at home and they are both running off of Windows XP. I also have my internet service through the local cable company. However I have recently purchased a wireless router and have attempted one evening to connect it however it was not wanting to completely set up and I have not had time to try it again. So, my actual question is I don't believe either desktop computer is wireless. So, when I get the wireless router to work will my other computer which isn't directly connected to the router and modem will it be able to connect to the internet with the "signal" receiving from wireless modem?