The highway from Paris costs 9.50 Euros. The train (sncf) from Paris to Troyes is about 25 euros for people under 26 and is hourly. There are also frequent trains to Reimes, Dijon, and Nancy.
The downtown area is easily walkable however to go to the outlet malls requires a car. From one side of the downtown to the other is probably a 30 min walk.
Troyes is located between to Paris, Reimes, Dijon, and Nancy making it an ideal base to explore the Champagne region. There are some lakes a short drive to the east of the city. The local football (soccer) team, ESTAC, is currently (2013 to 2014 season) in the second French division. Get tickets in the supporters section if possible as it is the cheapest and most exciting. It is very safe. Troyes has some of the best examples of preserved medieval houses in all of Europe, attracting many tourists. There are many old Churches throughout the city and wandering down the stone cobbled streets can make you feel like you are back in time. Besides this Troyes has some nice parks and squares. The Seine river runs through the city, dividing the downtown area roughly in two, and in nice weather you can sit beside it and sip some coffee.
Troyes has the usual selection of things to do. A great mediatech, ice skating, a movie theatre, lazer tag, bowling, pools, and 4 museums. Musée d'Art moderne, Musée Saint-Loup, Musée de Vauluisant, and Musée de l'Apothicairerie. Saint-Loup is the best but they are all worth a look depending on your taste. For more information see http://www.musees-troyes.com/
Marques City is located a short drive from the downtown area. It is an outlet mall with some good deals on clothing from famous French and international brands. It has probably the most stylish children and preteens in the world. It attracts shoppers from all over France and is an easy drive from the capital. Also there is the McArthurGlen Factory Shop Centre but I have never been there so can not vouch for it.
Rue Emile Zola is the main shopping street in the city proper and has a good selection of stores.
Giuseppino (26 Rue Paillot de Montabert) has the best pizza in the city but can be very busy during dinner.
In Sainte-Maure (9 km north)
In Bar-sur-Seine (32 km southeast)
The main bar area is the Rue Champeaux where there is the James Joycee, an Irish pub chain, it is okay but a little expensive. The best bar is probably the Bougnat Des Pouille (29 Rue Paillot de Montabert), it is generally a wine bar. If beer is your thing check out Pub Elixir (27 Rue Raymond Poincaré, 03 25 81 63 44) where the owner usually has cool beers on tap, often they are very strong! There are sometimes shows at the Elixir. The best nightclub is Cotten Club. Manhattans is a decent bar with a dance floor and while it usually has an older and local crowd they are friendly and often have special events. While the Troyes region does not produce its own champagne there are many places to taste it.
Best Western De La Poste has a good location and a great bakery across the street, go there do not pay for breakfast. La Maison de Rhodes is very nice and in an amazing building. It is the best hotel in Troyes but it is expensive. Hôtel Le Splendid or Hotel Arlequin are better for those on a tighter budget.
Lac d'Auzon-Temple and the Lac d'Orient are two man made lakes to the east of Troyes which are used to control the water levels of other rivers, they are very nice in good weather. As noted above Paris (west), Nancy (east), Dijon (south), or Reimes (north) can be reached for a day trip by car or train. The outlet malls mentioned above also have some good deals.