Originally Posted by
number_6
These questions have been well discussed already, but to save you time searching, yes and yes. The first carrier on your ticket is required to ticket, but any OW carrier can issue the ticket (or can refuse to issue it, their choice). Most will issue it if they fly a trans-oceanic leg. AA is usually the preferred ticket issuer if you have a choice.
number_6 is quite right. I would add that I use AA for these tickets for two reasons. First, the AA RTW desk is very easy to deal with. For example, as you may have read in other posts, I sometimes call them daily for weeks on end trying to get space on particular flights. They are never bothered by this. Second, AA's fuel surcharges, etc., tend to be less than those of some other carriers.