I stayed at the Hotel Ariston for two nights in October. It is conveniently located less than a block from Larissa train station and the metro subway stop. There isn't much in the way of restaurants in the area. There is a decent coffee/pastry shop called Everest next to the train station and a supermarket across from the Hotel Oscar. The neighborhood safe, but there are homeless people.
The hotel is small, but recently renovated. My room was small, but clean. Beds are hard. But I've found this to be true across Europe. One drawback for Americans would be the way you turn on the lights. Your hotel key is a card that you place in a card holder. That controls the lights. If the card isn't in its holder, the lights or TV wont go on. So, everything is turned off when you leave the room with the key card. I had this type of key card for two hotels in Athens.
There wasn't a big selection for breakfast, but it was tasty. There was good yogurt, honey, fresh fruit, feta cheese, ham/cheese slices, fresh bread, fresh fruit, mini cheese pastries (which as popular in Greece), juice and as much Greek coffee as you could drink.
This was a very nice hotel, reasonably priced. It's easy to hop on the subway and get to the Athens nightlife as well as all the tourist attractions. I stayed here because I needed to catch the early train to Kalambaka.
One last drawback, it's a hotel. It means that you will hear doors slam at all hours. You will hear talking and you will hear street noise. Athens is noisy. These are not quiet rooms. This is something you learn to deal with if you travel in Europe.