The Studio and New Playwrights' theaters are presenting plays about hearth and home, each an eccentric look at family life. At the Studio, Lanford Wilson's "Fifth of July" -- the better of the two shows -- treats the Talleys, a distended family featuring a legless Vietnam veteran named Ken, his homosexual lover, Ken's sister and her precocious daughter, plus daft Aunt Sally and her late husband Max: this last a pile of ashes she carries around in a box. "Stopover on Whitney Street" at New Playwrights' -- four slices of life in a tacky, yellowed kitchen -- is Peter Perhonis' brand-new comedy about a tribe of long- winded Greeks. Wilson's 1978 play is more slickly made, and the Studio is giving it a handsome production. The Talleys and their drug-crazed visiting friends have charm to spare. But the playwright's low-key depiction of misfits in Missouri occasionally strains credulity. You'd think that Ken -- a fellow, after all, who lost his legs in Vietnam -- would be somewhat embittered, perhaps even a tad neurotic. But as played by Bob Higgins, he's as well-balanced a character as ever worked the boards. You might expect his 57-year-old Aunt Sally, no matter how free-spirited, to be thrown off balance by Ken's openly physical displays of affection with lover Jed, or with the profligate pot-smoking and cocaine- snorting that otherwise goes on. But the Talleys according to Wilson -- and Sue Crystal's direction -- are as insistently unflappable as Ward and June Cleaver. The doings are set, on the occasion of a July 4th family gathering, in the large and comfortable Talley farmhouse -- nicely evoked by designer Russell Metheney -- in Lebanon, Missouri, a rural backwater brimming with rednecks. It develops that Ken's rich friends, both seemingly loyal college pals, want to buy the homestead for use as a recording studio; Ken's indecisiveness over selling the house -- and Aunt Sally's over whether and when to dispense with Max -- make for dramatic backdrop as the play moves toward a neat climax. Among the treats are Erika Bogren playing Shirley Talley, a 13-year-old apsiring femme fatale -- who manages to be a wise- acre without being a brat -- and Nancy Grosshans' likeable performance as nutty Aunt Sally. As Gwen, one of Ken's college friends who happens to be a copper heiress, Rosemary Walsh convincingly portrays a brain-fried space cadet who suddenly gets very sharp when it comes to protecting her finances. No one, alas, seems terribly sharp in "Stopover on Whitney Street." Unfolded in four vignettes, the play spans the decade from 1948 to 1958 in the Kostas family of Amherst, Massachusetts. The father, Vasily, is an ill-tempered carpenter given to heavily accented shouting. His wife, the ever-patient Irene, stands by to calm him down. Two strapping sons, college-kid George and soldier Gus, regularly appear to get Dad started again. What they lack in charm, the Kostases make up in noise -- "It's not your face, Pop, it's that voice of yours," Gus complains -- while delivering homey speeches on the meaning of this and that. "And another thing, Mom," says George (Buzz Roddy doing a deadpan that recalls the late Jack Webb) midway through one peroration. "You might remind Pop why Gus joined the Army in the first place." I, for one, didn't need to be reminded. But judging by laughter and applause, some in the audience found "Stopover" inviting. FIFTH OF JULY -- At the Studio Theater through June 19. STOPOVER ON WHITNEY STREET -- At New Playwrights' Theater through June 5. ort w