Hola, although it has only been a month since my visit to Guanajuato I can not recommend any of these hotels as I stayed at Hotel de las Poesias . . . . what I can say is that three times I ate at the restaurants bordering the Jardin de la Union and did not have a bad meal. The mentioned hotels all looked nice and are very central, if that helps.
I stayed at the Hosteleria del Frayle which is about 2 blocks maybe. Any hotels near the Jardin de la Union (Guanajuato's version of a plaza) would be close. I searched and found these nearby hotels: Casa Mexicana, Hotel San Diego, Posada Sante Fe, Hotel Boutique 1850, Ahuehuete Hostal Galeria. You'll enjoy the Museum and Guanajuato.
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