Don't have any specific cheese suggestions: but my new favorite accompaniment for the cheese plate is honeycomb! First had it over warmed goat cheese and it was amazing, tried it now with several cheeses.

You don't have time between now and Friday, but there's a great cheese vendor at the Rockville/Bethesda farm market on the weekends. They'd be able to set you right up.
WF also has a great cheese section, with very helpful folks.

Calvert Woodly in Van Ness has awesome cheeses, spreads, and wines.

When you do something like this, I think it is always most fun when people get to taste cheese that is unfamiliar to them, and with the wide selections you can find at so many places, it is good to branch out some. At Whole Foods, you can always find some local cheese from MD or VA, generally mid-priced (not cheap), and a double gloucester rather than cheddar from England can be a bit different. I would steer clear of brie, which has very little taste and is very familiar -- this field is wide open, do something fun.

For your blue, you can't go wrong with Humboldt Fog!!

Except Humboldt Fog is not a blue. It's a goat cheese that's done in the style of a morbier -- with a layer of ash in the middle, separating one layer that's a little more ripe than the other layer.
It's not an actual morbier, which is a cow's cheese. It's a soft, edible-rind goat cheese.

It is yummy, though.

There are also good stinky non-blues. Taleggio is a really good one. Grayson is similar to Tallegio, and from Virginia.

I saw an apple cinnamon goat cheese today at TJ's that looked AMAZING! I always do mini toasts and the crispest apples I can find, sliced up, with my cheese plates. And a good standby that the less adventurous eaters will like- a good English cheddar, havarti with dill, Brie, something "safe" like that. And I love to serve my mil's homemade peach and pepper jam with the Brie!

For your blue, you can't go wrong with Humboldt Fog!!

With all of these great suggestions, I would serve a Riesling. Second choices would be Moscato, pinot gris, or a rose. (For red lovers I'd have a pinot noir available, but I wouldn't push it.) Riesling goes with all of this and is a nice, light, low-alcohol start to the evening.

Save your heavier reds for dinner or after dinner. They would overwhelm a nice cheese board like this one.