Nobody mentioned Sunnin in this thread, so I'll put that into play. They serve very good shawarma and other lebanese dishes. The falafel are not that great, so I'd avoid that. It's definitely cheap, it's definitely in Westwood, and it definitely serves dinner. That would seem to cover all of the OP's criteria.
I've tried most of the Persian restaurants in Westwood and the standout for me without a doubt is OAHAM GRILL. It's located in a strip mall on Santa Monica at the corner of Sepulveda where the Coffee Bean is. They give you a wonderful complimentary humus with pita to start. I always wind up with the Cornish Hen which is absolutly delicious! Entrees come with rice and salad all for under $15 dollars. The owners are very friendly and it's quick take out too.
Skip Eurochow and Palomino altogether.
Cheap and good dinners:
Saks Teriyaki on Glendon
Noodle Planet on Westwood
Lamonica's New York Pizza on Gayley
Mongols BBQ next to Lamonica's
Medium price range:
Moustache Cafe on Glendon
Tanino on Westwood
Napa Valley Grille on Glendon
Nine Thirty at the W Hotel
Tengu Sushi on Lindbrook
I like Pomodoro's (not the chain). It's on WEstwood boulevard next to another Italian place, Sprazzo's. I prefer Pomodoro. Excellent small pizze, risotto, the pasta dishes are quite good. The ossobuco is decent, a little rich - (I like a lot of gremolata in mine) and it has a lovely ambience. Averages about $20 a head including tax and tip.
Down the street, Shahrzad is my fave Iranian. Don't know how many in your party - I'd suggest ordering the kashk-e bademjan appetizer, a shirazi salad (everybody shares these) and then a fesenjan and a polo, my fave is the estamboli polo, but the zereshk and albaloo polos are very good (I think there's also a shirin polo). Also, ask for onions and butter with the house bread straight from the tandur.
For dessert consider the faloodieh or persian ice cream.
1393 WESTWOOD BLVD
1422 WESTWOOD BLVD
If you don't mind a casual place, (open until 10 P.M.) Damon and Pythias, (see link to their web site) has just had some really good reviews on this board, (http://www.chowhound.com/california/boards/losangeles/messages/170709.html).
if you're looking specifically in westwood village, i would say perhaps tanino (italian). the other "nicer" restaurants (eurochow, palomino, tengu, napa valley grille etc.) in westwood village are *eh*
if you can venture down westwood bouelvard, try shamshiri grill. i love it!
re: the delicious life
I concur with the Tanino rec if you're limited to Westwood Village.
That said, Tengu, Palmoino and Napa Valley Grille are all just *eh*. Eurochow is the most egregious waste of real-estate I've seen in a long time.
I personally go for the Dinner of Champions: kimchi burrito at Jose Bernstein's, and then across the street to Diddy Riese for a huge $1 ice cream sandwich.
re: Das Ubergeek
South of Wilshire for restaurants are far better bets than the Village - either side of the street down to SM Blvd are Italian, Greek, French, Persian, Indonesian and now 3 Indian restaurants.
We're off to Shamshiri tonight for my favorite Tues. special, lamb shank with dilled fava beans (can't remember the Persian name but its plate licking its so good - however you can't make it down to the plate on one sitting because the portions are so huge).
re: the delicious life
i whole-heartedly concur with shamshiri grill.
the food is very good, and the quantity/quality/price ratios are EXCELLENT.
it also helps that they have a section of their menu devoted to vegetarian offerings so that there is plenty to chose from if your party that includes vegetarians and meat-eaters.