It kinda depends on whether you want to spend time sightseeing in the city or just a place to sleep near the Interstate. There are a bunch of quality motels around the intersection of Shallowford Rd and I75 that offer close access to lots of restaurants & facilities such as Hamilton Place Mall.
I believe another SpyderLover stayed at the Choo-Choo Hotel (historic location) downtown and that would put you in close touch with all the attractions in town plus numerous restaurants. Chattanooga downtown is a very nice area for tourism.
http://www.choochoo.com/
Plenty of places to ride near Chattanooga without even heading out of town very far.... starting with the Lookout Mtn scenic highway that runs all the way to Gadsden Ala along the mountain ridge. Not very far from here to head up into the TN/NC mountains as well, easy day trip.
Hope you will join us for a ryde while you are here and we can show you around town as well...
PM me with any questions but be sure to let us know when you are coming and we will plan to get together.
We are always looking for visitors to the area and have had a bunch of S/L visitors here in the past.
Jack