Nashville is a hoot. Did you know that it is now the top destination in America for hen parties? You'll probably see quite a few large groups of women parading around town, enjoying all the sights. They are especially funny when you see them on the 'pedal taverns' which are big carts where the riders drink and pedal around town as music blasts.
There are several tours that are popular:
NashTrash - two bawdy Dolly Parton-esq comediennes who do their act while you see the sights.
The Trolley - never done it but think it is more informative and sedate.
There are also various tours that take you around town and show you where some of the stars live - nice for getting a sense of the city outside of the tourist area - think Greyline is one of the popular ones..
You can take a boat ride on the river on the General Jackson. I think it starts out by the immense Opryland Hotel (which is out of town a bit), but near a huge outlet shopping mall called Opry Mills. Or you can plan to shop a bit there before you go to the Grand Ole Opry - it often happens in a venue near the Opryland hotel. By the way, if you have time, walk over and wander through the hotel. You'll be amazed at the size. it is one of the largest convention hotels in America, and is VAST with various ares of dancing fountains, gorgeous greenhouse vegetation, etc. But, don't try to eat there. It is expensive and not very good.
For food:
Everyone thinks they have to try BBQ, and I'd suggest
Martin's (several locations - one downtown, one on Belmont Blvd)
Peg Leg Porker
Edley's
Another big food 'experience' is hot chicken. If you go to Hattie B's on Charlotte, you can cool your mouth down with an ice cream from Bobby's Dairy Dip - but be sure to check the hours because they close early.
The other place for hot chicken is Prince's, but it is not in the best area if you're going at night. At both places, stick to the milder versions or you'll be in pain.
For breakfast, the traditional places are
Pancake Pantry in Hillsboro Village
Biscuit Love - think there are a couple of locations now
Be prepared to queue at both places.
Also, if you want to go out of town a bit, venture out to the Loveless Hotel. They have wonderful breakfasts, but also are known for their fried chicken and southern biscuits (like a dinner roll) that you slather on peach or strawberry preserves. But it is a bit of a trek out of town - maybe 30 minutes? Open for breakfast, lunch and dinner. They also have a shop there where you might find some funny Nashville items.
One final food thought: Nashville is know for its' 'meat and three' places (meat and 3 different vegetables on the side). Try Arnold's Country Cooking. It is not far from downtown, and looks like a dive, but is worth it.
If you're in the market for cowboy boots, this place used to be the best / cheapest and was a bit out of town, but they've moved and I don't know if they are priced as well anymore...but worth a look:
www.nashvilleboots.com/store.htm
There is also a Frye boot store in the Gulch near the Thompson Hotel (have a drink on their gorgeous roof terrace if you want to mingle with the young, trendy crowd).
I second the suggestion of the Country Music Hall of Fame Museum. Definitely worth a few hours. Good souvenirs in the museum store if you can find the gems among the tackiness. Also, be sure you wander back toward the Hatch Show Print store. It is very interesting and you might find some good souvenirs. Also, definitely do the Ryman Tour.
If you want something a bit different, there is a scale size replica of the Parthenon that is worth walking around. It is a mile or two away from the downtown strip, but not too far.
For music:
Downtown go into Robert's Western Wear. It is a cool place and easy to be there as a single woman. You should also walk up and down the strip and peak in at various places - definitely go into Rippy's but you should also go into Acme Feed and Seed - near the river. The ground floor is loud and touristy, but go to the second and third floors - you'll get a gorgeous view from the roof.
Check out the music at the Station Inn to see if anything good is on. You're likely to hear some good bluegrass / traditional music there.
And for what it is worth, I wouldn't bother with the Bluebird Cafe. It is over-crowded now that it was featured so prominently in the telly show, and the lines you very long for such a tiny place. You won't want to stand in the heat in August.
Try to walk over the pedestrian bridge downtown - toward the football stadium. It will give you a great view of the city lights.
I'll come back with other suggestions if I think of them. Whew! Did you say you're coming for 2 weeks? 