You swear you've seen the vinyl-covered table tops and austere Oriental decor before. Like a plain Jane with lots of charm, the Thai House Restaurant isn't much to look at, but the Thai specialties it offers often make up for its physical plainness.

"Hot" and "spicy" are understatements here, and dishes that are labled as such can be searing. Among appetizers, the spicy charcoal beef -- thin strips of lean, good quality meat served on a bed of lettuce and onions -- had a coating of spices fiery enough to make a dragon pause. Likewise, the fish-and-lemon-grass soup, a flavorful broth flecked with lemon grass, lime leaves and chunks of rather rubbery red snapper, was ablaze with red pepper.

Portions are generous at the Thai House. Appetizers -- enough for two to share -- and entrees are priced similarly, and none are over $6. But you'd be wise to put your money on the appetizers, most of which have proven better bets than the entrees.

Among the best of the lot was an enormous Thai egg roll stuffed with sausage, crab, egg and fresh crunchy bites of cucumber, scallion and bean sprouts. Wrapped in a delicate, paper-thin casing and coated with a sweet brown sauce, it suffered only from arriving less than warm. Pork satay, skewers of meat dusted with curry spices and served with the traditional peanut sauce and a side of cucumbers and onions, was very tender and flavorful.

Especially good was the Thai House Special Chicken -- four wings stuffed with bean thread and batter-fried -- which arrived grease-free and with a wonderful, crunchy exterior encasing juicy chicken bits. Among the soups, I'd stick with the chicken-coconut milk, a rich and aromatic broth with a pronounced ginger-lemon flavor, loaded with chicken.

Not all appetizers would warrant a repeat order, however. The Thai House Special Salad, for instance, was less than special: an unimpressive platter of iceberg lettuce topped with pink tomatoes and sliced, hard-cooked egg. Only the ground peanut dressing saved it from anonymity. Likewise, what the menu calls crab balls were closer to low-grade sausage patties in taste and texture: dry, flat and unpleasantly chewy.

Noodles -- egg, rice and cellophane -- are a Thai staple, and there are at least 15 such dishes on the menu. Of those sampled, Spicy Thai Noodles were by far the best: delicate, crisply fried and combined with bits of lemon grass, scallions and pork. The wonderfully balanced seasoning combination of that dish was lacking in other noodle dishes, notably the chow foon, a bland platter of broad rice noodles topped with an undistinguished and too-thick brown sauce.

Entrees that stray from the Thai classics have been less than exciting. The sweet and sour beef was a timid version here, neither sweet nor sour and lacking proper seasoning. And an order of roast duck was not only fatty, but cloyingly sweet in its sauce.

No longer is it enough for area Thai restaurants to serve a decent satay and leave it at that. As diners become more familiar with the intricacies of this cuisine, the increased competition among Thai eateries is often realized in prettier surroundings and expanded menus. With almost 100 dishes to its credit, Arlington's Thai House fulfills that expectation. And while some of these dishes are very good, keep in mind that quantity doesn't necessarily beget quality.