I'm not really a sweet person, so my fave snacks are of the savory variety!
I love the spicy cheese stuffed pretzels. Not the ones with the cheese dipping sauce, but the ones with the cheese inside. You get them at the Launching Pad in MK and at DHS to the left of the hat.
I love the eggrolls. I think the MK cart may have closed, but you can still get them at Epcot and AK.
The McD fries are always good.
I love the nachos in Mexico at Epcot and the lamb wrap in Morocco. The Morocco hummus is also amazing.
The pulled pork sandwhich at Flame Tree in AK is also very good (don't know if that constitutes a snack!)