Hi Matthew!
Traveling the "world" solo can be lots of fun and has its advantages. You'll never feel alone though because you'll be among friends.
Cinderella's Royal Table and Be Our Guest Restaurant are both excellent choices but if I had to choose, I'd tie a napkin around my neck and put their service to the test at Be Our Guest Restaurant. Its new - its beautiful - the food is great! I think you'll feel right at home there. And Guests over 21 have the option to enjoy their dinner the way lots of people in France do - with a glass of wine.
Be Our Guest Restaurant is super popular so I'd recommend you go ahead and make your reservations. You can make your reservations online at the link above or by calling 407-WDW-DINE. If you can't get reservations, try walking up. I have gotten in lots of places traveling solo.
Going solo can be great fun! You can do what you want to do when you want to do it. Its easier to navigate the parks when you're traveling solo. Its also easier to get into restaurants without reservations. I've had great times sitting at counters or bars to eat my meals at restaurants that have them. Its fun talking to other Guests & Cast Members. Be sure to take advantage of the single rider lines at those attractions that offer them. Don't forget to take photos & get in them. PhotoPass Photographers, Cast Members and other guests will be happy to take pictures for you.
Wishing you minnie magical memories :-) Allison