HWY 1 and 101 are LONG roads, so it depends where you're going between, but here are some top stops for you to consider..
In Santa Barbara, this is a LEGEND for amazing, cheap Mexican food. I think it was Julia Child's fave.. high and low brow drive from all over to go. It's really, really good!
-La Super Rica Taqueria- 622 Milpas St, SB, 805-963-4940
-In Woodside, a tony enclave off Skyline Highway 35, which (map it) isn't too far from HWY 1 between Santa Cruz and San Francisco..-http://www.alicesrestaurant.com/ another iconic joint.. owned by a gal named Alice, but immortalized in the Arlo Guthrie song. I've never been, but peeps love it.
-Between Santa Cruz and San Francisco, a mile off HWY 1, is a super cool place called the San Gregorio General Store. I LOVE this place. Been there since the 1800s, the crowd is a batty mix of Harley riders, long distance bicyclists, jug-band players, farmers, yuppies.. it's GREAT. On weekends there are bands, they have a bar, bad coffee, egg salads, cow milking tools, overalls, great books books, rubber boots, seeds... totally fantastic and very close to a beautiful beach, San Gregorio.
-In Ben Lomand, a little woodsie town just outside of Santa Cruz, there's an insane joint called Ciao Bella. Cabaret shows, ok food, and a total scene of nuts.
Ciao! Bella!! Italian Restaurant and Cabaret in Ben Lomond, CA
-North of San Francisco, in the awesome town of Pt. Reyes Station, there is a good dive called the Pine Cone Diner, but also, the Bovine Bakery is amazing. In this town, there's also a fantastic and highly regarded cheese company, the Cowgirl Creamery (though not a restaurant, nor divey)
That's my list. I'll post again if I think of more. Let us know where you're starting and stopping.. that'll help. Happy traveling!