No! The processor is soldered with the logicboard/motherboard. they only way to change/upgrade the processor of a macbook pro is to do it when you purhase new macbook pro. hope this helps...
If you have a new macbook pro with the metal body case, no. If you have an older macbook pro, you can use a coin to turn the lock on the bottom of the laptop to remove the battery.
No.
New Macs all have the same software installed. If you are referring to Garageband (See links below) then yes both the MacBook and MacBook Pro have it installed.
MacBook Pro is the best you can get
This is entirely dependent on the year of the MacBook. The new 13" MacBook Pro Retina keyboard is not the same as the regular 13" MacBook Pro. You also wouldn't be able to interchange a keyboard from the older 13" MacBook models (white MacBooks) with a recent 13" model.
Noplace.
MacBook Pro!
The macbook pro!
The Intel Core i5 offered in a new MacBook Air is more than sufficient for daily use. A MacBook Pro is better suited for heavy design or developing use.
you probably should get the MacBook. they are cheaper than the MacBook Pro. now, if you want a bigger screen, then get a MacBook Pro.
There is no age limit for getting a MacBook Pro.