DANCER, TEXAS POP. 81 (TriStar, PG) Four of the five seniors graduating from this blink-size West Texas town's high school plan to leave for Los Angeles just as soon as the next bus comes in. They've been planning to escape since they were squirts playing in the orange sun. Texas-born writer-director Tim McCanlies has a loving touch, and his sketches of the boys, with their contrasting family situations, are sweet and sharp: John (Eddie Mills) comes from taciturn ranching folks; nerdy Squirrel (Ethan Embry) copes with an alcoholic dad; Keller (Breckin Meyer) is an orphan living with his widower grandfather; Terrell Lee (Peter Facinelli), the son of strivers running a struggling oil business. Dancer is another one of those little woebegone towns that time forgot, its own little Last Picture Showplace, but McCanlies has the good taste not to cutesify or overplay its appeal. The address is just a fine speck of Americana, where some folks stay, and others leave to become filmmakers. B --LS