Well Disneyland gonna take a lot out of you, get to California Adventure if you can so you can drink
There's a gourmet taco place across from Disneyland called Puestos that I highly recommend, pricy for tacos but you on vacation so why not. There's also a couple nightspot places at a place called Garden Walk nearby if you looking to do something after, really only weekends though.
But since you out here with your girl you gotta make it out to Laguna Beach, quintessential OC that you see on TV. Anaheim is really just an extension of LA. My favorite beach is 1000 Steps Beach, gotta head down about 200/250 stairs to get to the beach but because of that it's fairly secluded and no little jits running around. Few restaurants nearby with a view including the Deck, The Cliffs, Driftwood. Again pricey but they on the beach in Laguna.
Huntington Beach - A lot people will say it's

and it is, but fukk em. Decent beach, Main Street has some restaurants and bars. The Bungalow is the spot all the cacs and asians set up at but it's a beautiful location so don't let that stop you
That's just off the top of my head, if you have anything specific in mind let me know