More current is better for quality as well as volume. The more current getting to a speaker makes it so you can play it louder obviously, but it also makes a more reliable power source so when you are playing it loud it won't destort. The best example I can think of is with a subwoofer in a car. If you have an amp that doesn't supply all the power the bus demands at a certain volume then the sub will start to distort because it isn't getting reliable enough power sent to it.
I've heard of people using that thick (usually orange) extension cord stuff found at hardware stores for long speaker wire runs. i dont know if thats what you had in mind but its something to look into.
you can use whatever kind of wire you want for speaker wire pretty much.
For a while I was using 2awg power cable from my amp to my subs, it was all I had. Didn't sound too good but worked fine.
Big thick wire for speakers is only good up to a certain point, past there the internal resistance of the wire itself starts to mess with you. Electrically, its fine, but acoustically it ain't too good.
If you need to do a long run (100 foot +) go to a good stereo place, they will have tons of advice to give you. They have special types of cable for really long runs. If you are over 250 foot you get to use those cool +17v convertors
you can use house hold wires.. you just have to make sure that the wires inside are stranded and not 1 whole piece...I use them as extensions to put my Creative LAbs DTT3500 around the top corners of my room.