I've stayed at the Continental several times over the last 10 years. Most often, we stay for a few days in December so we can visit the Christmas Fair in Romer, 2 S-Bahn stops from the hotel. The Frankfurt fairs are the best in europe, I've not been to all of course, tho of the several I've attended - Frankfurt the most entertaining fair. I've also stayed for business visits to AutoMechainika, also just 2 stops from the hotel.
when you walk out of the Main Railway Station entrance down by the food court and cash exchange, you can see the hotel - so just a <5minute walk. They offer nice rooms for a couple, also when alone I take a single room, which is very cost effective and a very unusual offering. Good access to all of Frankfurt as most of the S-Bahn and U-Bahn lines converge at the main train station