you could edit the order table so that the ID starts at a different number than 1:
ALTER TABLE tblName AUTO_INCREMENT = 12000
this would start the ID numbers at 12000 and each order placed would increment from there.
using a bar code in the emails would take custom coding to accomplish and is not supported.
Last question, in respect to your response, can I create an ID that has alpha character included i.e. event name-277 (ticket number) so that the end receipt number would look like
Receipt: staxx-277 and auto increment or decrease? My goal was to have the cart read sold out after say 300 tickets have been sold, so the starting ticket receipt would read "show name - ticket starting number i.e. staxx-277, next ticket sold would read staxx-276 etc. Once all of the tickets have been sold (staax-001) no more payments could be received and some form of sold out notification be displayed?