2 PCs, 1 Laptop, HiSpeed Cable, Vonage phone

Goal: A way to utilize my Comcast cable Hi-Speed Broadband internet connection with: 1) two PCs (one upstairs, one downstairs - opposite ends of house); 2) laptop w/built in wireless; and 3) Vonage broadband phone.

Specifics:
Upstairs PC has Windows XP Pro, no wireless network adaptor
Downstairs PC has Windows XP Home, no wireless network adaptor
Laptop (HP) w/802.11g wireless built in
Hi-Speed cable connection currently located on upstairs PC, along with Vonage modem

What would be the best way to accomplish my goal without compromising performance, speed, etc.? What specific recommendations for equipment do I need?

 

Vonage has it's on Linksys router.
The 2 PCs are too far apart for me to connect ethernet cables from each (one is upstairs, one downstairs, both on opposite ends of the house). That's why I thought about wireless, but I'm thinking the distance will be a problem..?
Are you saying just one router for both PCs? What's the ethernet switch all about?

 

Distance within the same house should not be a problem. A switch is a physical extention of the router allowing multiple wired connections.

You will have to connect one of the machines directly to the router to begin with in order to configure it.