I think a lot of the Tarrytown fest dpended on whether you had a car or not. They dodn't have great lunch service available. Again, I need to warn first time attendees, that DS conventions are designed for people who don't have meals betweem 9:00 am and 9:00 pm
No joke!! If you are hypo-glycemic, take a bagged lunch in the main room w/you and plenty of snacks, water etc... However, if you're on your 3rd, 4th, 5th or beyond Fest, you've pretty much seen all your going to see and can pick and choose what you want to see and when you want to leave to go eat.
Really, Tarrytown had a nice diner down the street
If it's the diner I'm thinking of--The El Dorado--they *are* pretty good and we've eaten there over the years whenever we make a road trip to Tarrytown/Essex/Norwalk/Newport. There was a deli down the street was NICE! We ate lunch and breakfast there all weekend. And the price was right! Their chicken salad was KILLER!
The Brooklyn Marriott has some good places to eat nearby. There's one street full of nice international restaurants about 2 blocks over, and the next block over had some take outs and Subway. The Brooklyn Marriott has a nice restaurant, but at Marriott prices, meaning breakfast about $20 per person. Nice for one day but pricey on day 3. Then again, there's the subway to Manhattan.There's also a nice pool and gym at the Brooklyn.
For some reason a lot of ppl didn't like the Brooklyn Marriot, I thought it was nice and like you say, there was a subway stop a block from the place that would take you in to the city.