I noticed they have an ethernet cable in the apple Store. My current one is shot, lost the latch that keeps it from coming out, and is twisted every which way. Does it matter what ethernrt cable one uses fro the MBP regarding the connection? I see they sell one that is not called an "ethernet" cable, but would it do any good for my connection is I purchased something like this or are ethernet cables CAT5 just the same as the next?
You should get cables that have all eight wires (and all eight gold contacts) in place. This kind is required for Gigabit Ethernet should you ever need it, and is generally NOT more expensive than the four wires cables. When I find four wire cables in my collection, I cut the ends off and turn them into scrap wire.
Cat 5e cables looked like they were going to be very important, but a different transission scheme won out, and now Cat 5e is only important for long cables.
"Plenum rated" cable is electrically identical to "Riser rated" cable but has a flame-retardent jacket. It costs twice the price, and is not required except for running above suspended ceilings in certain cases.