To add to the discussion of which "foreign" Disney park to visit first; that decision should be based on which country you would rather visit. The parks can easily be experienced well in a couple of days, and with the cost/commitment that comes with overseas travel, it makes sense to couple the Disney park with a larger trip.
A very good point.
My comments were on the typical American snowflake (love how that term has become so in vogue these days) who has never traveled abroad and wants to largely to visit Disney parks. But even taking that away, I would still advise France as the first place to visit (or second if you include a UK component!)