I believe my home has two wires connected to each phone jack. The other two are not connected. If I want to get DSL do all 4 wires need to be connected? If so, is this something you can do yourself? Thank you!

No, two wires are enough. DSL is transmitted over the standard telephone wire. The other two wires are unused and are there for when the same cable is used for a different purpose. Cat5 cable used for Ethernet has eight wires but in normal use only four are used. It saves having a different cable for every use. The same cable can have multiple uses. Stuart

Pardon my curosity but is this in any way related to your using DSL splitter setup with Wilcom PS15, as discussed HERE? i_Xp/VistaUser

Thanks for your responses. Yes, this is related to my earlier post.

The standard 4-wire modular phone cables work with single or two line phones. Single line phones only need 2 wires and just ignore the other 2. Two line phones need all 4. Most houses have 4 or 6-wire cables running through the walls but the jacks themselves are often connected only for a single line. So when adding a second line you need to pull the jack out and hook up the second pair of wires.

Thank you all for your responses! I was a little confused with standard telephone wiring and CAT5 wiring I quess! Anyway my home only has a single line so, as you described, I only need two wires connected.