Also, periodically check the Rainforest Cafe website or get on any mailing lists they have (and join their Facebook page), as they will occasionally have good coupons you can print to get $$ off your food at RFC (and RFC has a much wider variety of menu options than most of the places inside DL or DCA). It may be even be worth joining the Safari Club, as you get a little discount every time you eat at RFC when you are a Safari Club member, as well as priority seating status.
http://www.rainforestcafe.com/
Ditto for ESPN Zone - join their MVP Club, which I think is free - and not only will that assist you in making reservations at the DTD location (or any other location), but I
think (I could be wrong) you can get little discounts with that too.
http://www.espnzone.com/
I have not yet eaten at Mimi's or Millie's, but they are both very popular among DIS-ers. Mimi's offers a coupon for free breakfast when you join their club(I think you have to purchase a breakfast to get the other one free, but could be mistaken on that). Check their websites for further info.
Mimi's -
http://www.mimiscafe.com/
Millie's (has a Best Guest Club and a Kids Klub) -
http://www.millies.com/
Naples, Catal and Tortilla Jo's are all owned by The Patina Group. Patina Group is currently offering a $30 certificate for any of their restaurants (including the ones in DTD) on your birthday if you sign up (for free) to receive their Simply Patina e-mail newsletter. Details are on their website.
http://www.patinagroup.com/joinus.php
Ralph Brennan's Jazz Kitchen (to get on mailing list):
http://www.rbjazzkitchen.com/
LaBrea Bakery (to get on mailing list):
http://www.labreabakery.com/index.aspx
I also joined all the Facebook pages for any Disney-area restaurants I was interested in, including Rainforest Cafe, Mimi's, La Brea Bakery and Ralph Brennan's Jazz Kitchen. I am sure there are probably also pages for California Pizza Kitchen and all the other places in Garden Walk nearby to DLR. I would suggest getting on every Facebook page and joining every mailing (usually e-mail) list for every place you can think of, as they will send out info and alerts of special discounts, promos or coupons here and there, all to your News Feed or e-mail.