I am confused buying over DVD player. Could you please clarify following points?

Do all DVD players are VCD players by default? Or they must show VCD symbol to state explicitly that they do play VCDs as well?

If a DVD player is made for zone 2 only, is there any way to make it zone free?

Some DVD players say they can play Kodak Photo CDs. Now what is exactly "Kodak Photo CD"? Is it just any CD consisting JPEG files? Or there is any special requirement of storing JPEGs in the CD? That is, if I create a CD by writing several JPG files in its root folder, will it become Kodak Photo CD?

In the market, there are several DVD players available - from £30 to £200. Their specs are more or less same. Then what is the difference between cheap and expensive DVD players?

In the back of most DVD players, I find following output sockets.
A yellow socket [for video]
a white socket [for left or mono audio]
a red socket [for right audio]
a orange socket marked as coaxial [what is the use of it?]
a scart socket [does it have any use outside UK?]

If my TV doesn't have scart socket [ie. it only has coaxial or R/F socket], can I attach a DVD player to such TV?

Any suggestion will be hightly appreciated, thanks a lot in advance!