February usually has the coldest weather and water temperature, but there’s still plenty of things to do. I’d suggest you walk around Heisler park, explore some coves during lower tides, hike Top of the World, and shop/gallery browse in downtown. For dinner eat at South of Nicks and for dessert eat at Gelato Paradiso. That should have you covered for touristy stuff.
Yelp is definitely your best friend here! Irvine is kind of an epicenter of food, so you’ll definitely have a lot of good choices. If you’re feeling Korean/Asian food, Diamond Jamboree is a must, and is very very popular here. The Crossroads has a kind of trendy atmosphere, with lots of desserts…
Honestly for fabulous views, you should go to Raya at the Ritz Carlton in Dana Point. It’s about 15 minutes down the PCH from Laguna Beach. Otherwise South of Nick’s in Laguna Beach does amazing Mexican cuisine and has some great partial views.
You didn't say North or South County, so here goes-
North - Blue Gold in Huntington Beach at Pacific City. Bonus, go or the sunset, windows overlook PCH and the beach.
Central - Javiers in Crystal Cove - Newport Coast - decent but overpriced Mexican however, it's a very cool place and they know…