We are vacationing in Greece in early September. We will be spending one night in Thessaloniki and would like input as to where to stay and what to do. We will have a rental car.
Also, on the way there from Nafplio, we plan to spend the night in some small village and stay in a B&B...any recommendation?
I'd recommend staying at the Excelsior Hotel which is around $130 and is beautiful with comfortable rooms and a great staff. www.excelsiorhotel.gr/luxury-hotel-accommodation.php#!at-a-glance
As for what to do there- there is a lot- for example, The White Tower, the Arch of Galerius, the monument of Alexander the Great, the catacomb of Saint Dimitrious, Aristotelous Square, the Archaeological Museum, Noesis Science Center& Technological Museum just to name a very few.
Almost every town in Greece has an Archeology Musuem, but the one in Thessaloniki is excellent! I stayed at Hotel Orestias Kastoria, a budget listing from Lonely Planet, however, you might want one that promises parking. If you have an interest in Turkey, you can also stop into the Ataturk birthplace house (well described in LP but not well marked on the street).
If you could push on 7-8 hours to Thessaloniki and stay two nights, you would have a full day of sightseeing in that city. I'm not familiar with the larger towns en-route, but they look fairly average. You might look along the coast near Lamia (rather than in the city). It should not really be critical to book ahead in September, especially with the flexibility of a car.
We're staying at the Electra Palace Hotel for an upcoming trip. It was recommend by people of a Trip Advisor forum--mainly for the excellent location. We will not have a rental car at that point in our trip however, so I don't know about parking options.