Toledo, OH is my hometown...so maybe I am a little biased. :)
I have read some of the reviews of Toledo...some accurate and some misleading. So I will attempt to clear those up and let you know a little bit about where the truly GREAT spots are in this city.
First of all, if you are staying downtown and expecting there to be alot to do (especially on a weekend), then you will be disappointed. As with most cities in Ohio, the downtown area is a M-F 9-5 kind of place. The main exception to that is during baseball season when the Mud Hens play downtown (minor league baseball). The Mud Hens are the true gem of downtown and are a MUST SEE if you are in town when they are at home. The area around the park also has a few nice shops and restaurants, making for a great day or evening of entertainment. Fifth/Third field (the Mud Hens stadium) was rated as the best in minor league baseball and last time I checked it was only 8 bucks for any seat in the whole place. International Park (across the river) is about the only other interesting attraction in the downtown area (until the Science museum reopens in 2009). There is a Great Lakes Freighter permanently parked there as a museum as well as some nice walking paths and a handful of good restaurants.
Next, the Toledo Museum of Art is probably the biggest gem in the entire city. It is a short distance from downtown on Monroe St. Absolutely one of the best art museums in the country, even for its relatively small size. Especially noteworthy are the Impressionistic works as well as the Egyptian and Antiquities collection. Lastly, the beautiful musical performance hall here is called the Peristyle and is a great place to see a symphony concert. It is designed to look like an outdoor Roman/Greek Amphitheatre. A truly unique place to see a performance. The best part about the art museum is that IT IS FREE!!!
The Toledo Zoo would have to be next on my list. It is compact and usually not overcrowded. Not to mention that many of the exhibits are either brand new or recently updated. Don't miss the new Africa exhibit...the animals are more free roaming instead of being in small cages. A great place for kids at a reasonable price.
For some good eats...you must visit Tony Packo's for the best chili dogs on the planet. Any fan of the show "Mash" already knows about this place. The food is truly unique and amazing. The dogs are more like bratwurst or sausages than regular hot dogs. Don't forget to try the spicy blend of pickles. The other sides (such as German Potato Salad, Kraut and Paprikas Dumplings) are also wonderful. There are even several locations scattered around the city, although the original on the East side has the best atmosphere.
Do you like to shop? I recommend several places (none of them downtown though). There are two new outdoor, upscale "malls" in Maumee and Perrysburg respectively, complete with the usual mall stores (GAP, Barnes and Noble, GNC, etc.) as well as more upscale stores at Perrysburg's Levis Commons center. Both are conveniently right off major freeways as well. For winter time shopping, you might try Franklin Park mall and the surrounding area. This is a standard enclosed mall, but it has been recently remodeled and expanded...making it a very full and beautiful mall. The area surrounding this mall has your usual strip mall fare such as Barnes and Noble, Circuit City, Toys R us as well as several nice restaurants.
I recommend Toledo's Metroparks as a great destination for the nature lover. Our parks are well known to locals but often overlooked by visitors. Try Wildwood with its beautiful Manor House or the enormous Oak Openings park with its ponds, tons of trails and even sand dunes! Lastly several parks along the Maumee River (Side Cut, Farnsworth, Providence) provide beautiful views and a great place to have a picnic or a short walk.
For nightlife, Toledo has the usual generic bars and clubs, but you might try the Valentine or Stanahan Theaters for something to do in the evening. Both have local productions as well as larger traveling shows (such as The Lion King, Phantom of the Opera, etc.). Also, as I mentioned, Toledo has the Mud Hens, a minor league hockey team as well as The University of Toledo Rockets for sports fans (with a beautifully renovated basketball arena brand new for the 2008-2009 season).
All in all, I believe Toledo is a diamond in the rough, you just have to have some insider knowledge on what is truly unique and worthwhile. Toledo definitely has some questionable areas to it, but if you know where to go and what to do, you CAN have a great time in my hometown.