As I'm sure you are aware what you are trying to do is a non-standard way of wiring telephone and Ethernet. The proper way to to this is to run separate cable for phone and Ethernet to each location.
Assuming you have chosen not to do that you can make what you are doing work. 10/100 Mbps Ethernet uses two of the four pair. Gig Ethernet uses all four so it will not work with your setup.
Ethernet cabling has to be point to point. At the wiring closest need to terminate the two pair used for Ethernet at an 8-pos jack (called a patch panel) and use a short cord (patch cord) to connect each drop to Ethernet Switch.
Maintaining proper pairing and using correct pin-out is critical to making Ethernet work. Transmit is on pins 1 & 2, receive on 3 & 6.
»plone3.trueblade.com/knowledge/e ··· -pinouts
»www.ertyu.org/steven_nikkel/ethe ··· les.html
I strongly recommend doing this right by running additional drops to areas you want Ethernet rather then using non-standard wiring.