Restaurant in No. Va. with tables for 8?
Not sure where you are looking - Northern Virginia's a pretty wide area.
Rabieng in Seven Corners (Thai) has an interesting large table upstairs that is sort of on it's own level. Homey Thai place.
Bombay Bistro in Fairfax has a fun table with low cushions for a group (instead of a traditional table).
Austin Grill in Burke/Springfield can accommodate groups easily - I like it better than Rio Grande
Peking Gourmet Inn in Seven Corners has quite a few big tables, some with lazy susans. I must admit I haven't been in years, but always enjoyed it when I used to go out with friends all the time. Not like the best Chinese food you'll ever have or anything, but I remember the Peking Duck and Szechuan Beef Proper were really good. Check a recent review though - I never see it in the magazines and reviews anymore - maybe it's gone downhill. But it used to be kind of a fun place for a group.
McCormick & Schmick's
Rio Grande Cafe
Bazins on Church in Vienna is a great little restaurant - give them a call and see if they can accomodate you - NOT a chain, great atmosphere and phenomal food!
Sweet Rice in Falls Church, VA is a great inexpensive thai restaurant - call and see if they can accomodate you
Coastal Flats/Sweetwater Tavern/ and any other Great American Restaurant CANNOT accomodate parties of 6+ unfortunately (you should go sometime when you have 6 ppl or less for sure - good eats!)