In laymans terms, is there any advantage whatsoever to having a higher amp battery, higher price to 1 side, lol??
AH = amp hours (how long the battery will "give" a certain current voltage)
You can get away with tiny capactities, see
http://www.golfmk6.com/forums/showthread.php?t=37547 (look up braille batteries)
CCA, the 480a figure in my post above, relates to starting current, the lower the temperature the more difficult it will be to supply the current to start the car.
I would recommend you stay around this figure with a replacement. But you can save lots of weight by reducing AH (DONT LEAVE LIGHTS ON THOUGH)