we went during my fiances birthday back in 2003, i had the akl guest services have goofy (prerecorded) call the room one morning to wish him a happy birthday. i also ordered a bday cake for dinner one night at le cellier steakhouse in canada at epcot. you can do this at most wdw restaurants by request, for a fee, call in advance though. some places to celebrate a birthday/special events is chef mickeys at the contemporary fun atmosphere, a wdw dinner show - my dad did this for my mom years back at the poly luau they asked here on stage & then sang to all bday celebrants, or a firework cruise. we did this for a romantic evening one night on the illuminations firework cruise, we also ordered food & drinks through yc catering. fyi - they have a bday cruise package. also mention its a birthday at resort check in & at restuarants you might get nothing at all but sometimes a happy bday wish or treat, my fiance got morethan 1 cupcake & happy bday.
you could also just do something special like a wdw tour - dolphins in depth, we had a great time on this tour & got a great photo souvenir; recreation activity - hayride, parasailing or spa treatment - we do this every trip, very relaxing. you can also buy some wdw related merchandise, like a personalized disney shirt through disneydirect.com or disneyinkshop aka zazzle.com for like $20, birthday pin or ornament at wdw or personalized plush through disneygram at disneydirect.com or floral bouquet or gift basket through disney floral.
hope you these ideas help! have a great wdw bday trip!
