Actors Jaston Williams and Joe Sears, currently starring in "Greater Tuna" at the Kennedy Center's Terrace Theater, claim Austin, Tex., as their "official" home, but both share yearnings for more open spaces such as the desert, mountains and the sea. Time off from the show, which they wrote, is short, and after a year and a half on the road they are ready for vacation.

Williams would choose:

* Taos, N. M. "I have a lot of artist friends there. It's truly beautiful, especially where the desert meets the Rocky Mountains. It's really an incredible combination when you have the Rockies looming behind you and the sun setting in the desert. Plus, I love Mexican food. I need a plate of enchiladas at least once a week or I have a problem."

* New York. "The big thrill for me in the city is being able to walk into a theater and see, say, James Earl Jones, right there up on stage. I love the Village and Gramercy Park area. I find the lower side of the island very quaint and charming . . . "

Sears admits, "I'm not a city slicker, but very much a country person." He would pick:

* Bartlesville, Okla., his hometown. "It's a Phillips Petroleum Co. town with elm and oak trees nestled around the Caney River. I can recuperate there by just walking along the river and taking in the sights of where I grew up. It's very beautiful."

* Port Aransas, on the northern tip of Padre Island, Tex. "This is a small fishing village just below Corpus Christi where I go to paint and fish off the jetties and piers. When the afternoon heat comes on, I paint seascapes in the sand dunes."