Hydroguy's A DLR Guide for WDW Vets might be helpful as you familiarize yourself with DLR. Be sure to check the entertainment calendar because not everything is offered daily (not even in the summer).
I also like to compare and contrast the attractions with the same names, but some are more interesting than others. For example, The Little Mermaid has some minor differences, but the main attraction is nearly the same; so if you're pressed for time, I'd skip ones like that. I would focus on the attractions that have the same name, but potentially some major differences (e.g., Pirates, Haunted Mansion, Jungle Cruise, IaSW, Buzz Lighyear Astro Blaster, Space, Splash, etc.). Soarin is back to the original movie (Soarin' over CA) right now, if missed it or want to see the previous version.
My favorite attractions (in no particular order) are Haunted Mansion, Pirates, Buzz Lighyear, Space, Matterhorn (although, it's really bumpy and rough), IaSW, RSR, and TSMM (this is pretty similar to the one in DHS).
In terms of food, I really like Plaza Inn (Fried Chicken), Jolly Holiday (the desserts!), Red Rose Tavern (Grey Stuff - which is different from the MK version), and Alien Pizza Planet (cute decor). For Table Service, my favorite is Cafe Orleans (pomme frites!).
If you're only going for one day, you'll have to decide if you want to invest the time needed for a nighttime show and then which show. I think you have a better chance of "catching" fireworks (
Disneyland Forever) with less of a wait than WoC. WoC is unique to DCA, but if you don't invest enough time to get a good viewing spot (where you can see the water surface), it's not really worth seeing (IMHO).
