209 is an excellent place to sit, a very small and quaint section. Our company has season tickets in sections 208 and 209; club seats so the seats are maybe 2 inches wider and a little more comfortable with a little more leg space. Almost like sitting first class on an airplane, the extra room is appreciated but not something you have to have to enjoy the game.
The rows in this section are lettered A thru L so there are very few steps to climb. If you're looking for a rowdy fan environment, you won't find it here. DC is full of businessmen and bureaucrats so that's the type of people you will encounter in these seats.

Of course, there isn't a designated "rowdy area" at Nationals Park. For example, usually the bleacher sections at other MLB ballparks is where you'll find the drunkest fans who just don't care nor know how to behave.