If you have one day..

I would spend my one day in the Magic Kingdom, possibly with a monorail loop of hotel hopping.
Yea, I'm boring like that.

One day I'd spend at Magic Kingdom. If I could park hop, I'd split the day between MK and Epcot.

If I had two days, I'd spend one at MK, the other at Epcot.

Dining options: Biergarten in Epcot. I've never done table service at MK, but we'll try Liberty Tree Tavern this October, so maybe there. Counter service would be Columbia Harbor House in MK and either Sunshine Seasons or one of the several World Showcase counter-service options in Epcot.

My one day would be EPCOT or split MK & EPCOT.
I'd have to do Test Track & Soarin then wander the countries taking in the shows - Voices of Liberty is a must. A little snacking along the way is good too!
I am in love with La Hacienda for dinner. We've tried the meat and mixed seafood for two and loved both of them. Chips and different salsas were great too.
If I were to be at MK for dinner, my love of Pooh & Tigger always make me return to the Crystal Palace. If it's hubbys choice we hop over to Ohana's for dinner.

Biergarten is perfect if you're dining solo at a table-service restaurant because you'll be seated with other people. So unless they're really antisocial or don't speak your language, you'll have someone to talk with during your meal. I did this last year - we had a Spanish-speaking family, an English-speaking mother and two daughters, and me in between. My Spanish is practically nonexistent, so aside from greetings I couldn't converse much with the first family, but I had a very nice time with the other family.

At Teppan Edo they'll also seat you with other parties. I can't personally vouch for that restaurant because we've never eaten there, but I've heard good things and have an ADR there during our next trip.

I'd probably go to HS and ride the daylights out of Rock N Roller Coaster And Tower of Terror and pig out on cupcakes at Starring Rolls Cafe and get me one of those cappuccino cupcakes that Jess told us about previously!

Though I could easily pick any one park and be perfectly content for a day. Dang, that's a tough question!!

One Day = MK, snacks and counter-service all day to max the time.

Two Days = Epcot and MK. 1st day at Epcot. I'd eat around the world for lunch, but have a late dinner at a sit-down. Rose and Crown is a favorite, but there are others that get good marks around here, too. MK Day just like before. Snack and counter service to max the time!!

Not boring at all! Sounds like a lot of fun. We love checking out the other Disney hotels. Gives us a good idea where we'd like to stay on future trips. MK is my fave park so spending the whole day there is perfect.

I've done all 4 parks in one day...I was really tired that evening but took advantage of the EMH. I see you're off property so i'd pick EPCOT and DHS. I love MK I just enjoy the environment at Epcot and the rides at DHS. if you have 2 days I'd do MK, EP and DHS.
Go at rope drop for DHS and hit the major rides. Then pop over to EP, The second day I'd spend at MK just soaking up the pixie dust.
As far as meals...I love the 50's at DHS, Anywhere in EP and I usually grab mini corn dogs and roam through MK. Cosmic rays is filling I tend to graze through MK although I do love the CP buffet.

If it's only day, definitely just go with quick service to make the most of the time. Magic Kingdom probably has the most to do in one day's time. Go in with a plan in mind for sure. And grab those little schedules next to the maps. Those things are so useful, but many people just pass them by.

Yep, BOG is a lunch possibility. You could do Be Our Guest for lunch and Pecos Bills for Dinner.

Animal Kingdom in the morning with a Yak and Yeti lunch

then head over to Epcot, eat at WS somewhere before ending the day with Illuminations

Epcot. My favorite park then MK for at least on ride on space mountain