Figured I'd chime in for my fellow H-Tineian.
Great recommendations so far. I'll add:
Herb and Wood (a Brian Malarkey restaurant): good spot for a nice date night in Little Italy. A few standout items: Sicilian crudo, roasted baby carrots, Iberico pork, filet, gnocchi, and strawberry souffl. Yes - I gained 7lbs during dinner.
Animae (Tara Monsod and Malarkey): great Asian fusion concept for which Tara was a James Beard finalist this year.
The Red Door (Hillcrest) for delicious and authentic Italian. Smaller, cozy restaurant with a sometimes lively bar next door (live music some nights). The chef/owner, Luciano, is from Milan and quite the character. He usually makes the rounds in the restaurant to check in with everyone.
Las Cuatro Milpas - SD's Irma's. Simple, traditional Mexican fare. Easy to get in Houston and Texas, so might want to go other places, but the food tastes like you crossed into TJ to eat.
If you're up in Oceanside and want a fast/simple/casual lunch, then Board and Brew will be perfect. Craft beers and good sandwiches in a place the size of a Subway. I haven't been to the one in Oceanside, but I've been to the Carlsbad location a couple of times.
Not too far from Oceanside (30 minutes) is Stone's west coast brewery/tap room/pub in Escondido. I'd skip eating there, but they have a nice outdoor area to sit out and enjoy a beer.
La Jolla / Torrey Pines - I agree to drive up the coast starting in La Jolla with a stop at the Gliderport. I always enjoy watching people run off of the cliff while hoping their glider works. Truly amazing to watch them up close. You can also wave to Alicia and Swizz.