Atmosphere: Wear something nicer than jeans although it's informal. Dancing every night from 10:30 p.m. to closing; disc jockey takes requests.

Hours: Monday through Thursday, 11:30 a.m. to 2 a.m.; Friday and Saturday, 11:30 a.m. to 3 a.m.; Sunday brunch, 11 a.m. to 3 p.m., dinner to 2 a.m. Food served every night until 1 a.m.

Price range: Most dinners are in the $5 to $8 range.

Reservations: Not taken for dinner.

Credit cards: All major cards accepted.

Special facilities: Side parking for handicapped, near handicapped entrance. Ring bell for service.

There are some major contradictions at Jasper's. Enormous attention and expense have been lavished on a stunning decor. But a few moments in the microwave seem to be all the effort expended on much of the food.

Families are welcome. The menu has children's dishes, the staff greets children warmly and there are specially prepared highchairs for babies. Yet we were told that the place is purposely designed with a huge open central bar so that watching people drink will be a form of entertainment.

Jasper's is a beautiful restaurant, however, and an interesting one in which to walk around. It's a bit of southern California in Greenbelt: lots of blond wood and green plants growing under electrically lit skylights.

There are fascinating niches. In one corner a raised hearth is surrounded by cacti and American Indian pottery. In another corner there is a display of excellent art posters; in another, embroidered tapestries. Backgammon tables line one side of the room, huge mirrors another, shelves full of books yet another. The place is a visual treat, and very engaging.

The 24-page bound menu is heavy on Tex-Mex taco variations, plus a lot of fried foods and novelty items with names like "steak on a stick," "steak stick shrimp," "chicken fingers" and "combo fingers," which are variations of skewered beef, chicken and seafood ($6 to $9).

There are also omelets, quiches, pastas, stuffed potatoes--in short, a range of past and present trendy short-order items, which can be good if the ingredients are fresh and the batters well-prepared. There's a good fry cook and the emphasis is on simplicity.

So we tried the Ultimate Nacho, for a starter. For a high $4.95 we got a plate of a dozen small pieces of limp taco thinly coated with what tasted like a mild canned meat sauce, melted cheese and canned jalape no peppers.

Our waiter warned us away from flounder amadine ($7.75), so we ordered crabmeat and shrimp mornay ($8.95). This was a large moon-shaped casserole of what tasted like canned shrimp, a few slices of canned mushrooms and some shreds of seemingly tinned crab, blanketed in a dense yellow mass into which a soggy onion ring was sinking.

Fried shrimp ($8.95) were large, but coated in a tasteless batter, crowded together with greasy french fries and another soggy onion ring.

As for the beef dishes we tried, New York strip ($10.70) was tough and sinewy topped by "maison butter" (according to the menu) that tasted odd--not like real butter at all.

The steak sandwich ($5.65) bought a limp London broil tasting as if it had been microwaved rather than charbroiled, served with canned bouillon not at all "au jus" as the menu had said.

To its credit, Jasper's puts together a very good salad: freshly prepared mixed greens with lots of romaine and other lettuces, fresh carrots and more. Unfortunately, the several dressings we tried were unpleasant, either too sweet or lacking any flavor other than oil.

We did not get to taste desserts, other than a few perfectly ordinary sundaes, but a waitress told us the carrot cake, cheesecake, peanut butter pie and apple pie are made on the premises (they range in price from $2.25 to $2.75).

In our experience, Jasper's food can't hold a candle to its looks.