The White's Ferry is a nice option, especially if you're heading to western part of Maryland. A Friday before a holiday weekend means it may take upwards of 2-3 hours to get across the American Legion Bridge and around past 270/Bethesda Rockville - that is the most horrendous stretch of road.
Herndon is another option as someone has mentioned Reston. There are lots of places around there. I think it's one of the first Dulles Toll Road exits it'll take you towards Route 7 and into Herndon/Reston, it's probably only 2 miles from the airport. Watch out for heading down Route 7 towards Tysons Corner as that gets very busy. We were meant to meet someone around 4 or 4:30 on a weeknight at Tysons and they were in Falls Church off the beltway, no more than 2-3 miles and it took them nearly 1 1/2 hours drive.
Basically think at least as bad as London traffic in the rush hour.
OOh, just found the most Awesome Mexican place, if that's your cup of tea, called Anita's, we used to go in Vienna and it is really awesome authentic.
701 Elden Street, Herndon, VA 703-481-1441
Also, if you like Pho restaurants (Vietnamese) there are 4 in Herndon (and millions in Northern Virginia, the "REAL" Virginia) Pho 75, Pho 99, Pho 2000 and Pho Herndon. I don't know why they generally have numbers after them but they often do for some reason.
It's all coming back. I haven't lived in Fairfax, VA in nearly 7 years!