Stayed both arriving in Frankfurt and before departure (Mid Sept and Mid Oct). The hotel was being upgraded during both stays - causing the elevator to be out of service on several occasions.
The rooms were clean on both occasions, no tub only shower, nice duvet, plain rooms, wifi (we used it successfully both occasions), weird locks as mentioned below (ok once you get the hang of us - they have a demo at check-in PAY ATTENTION, depending on which way your door opens also affect which way to turn the lock).
We ate at a restaurant nearby - reasonably with good food - several to choose from.
Breakfast was good - eggs, meats, cheeses, various breads, butter, coffee, hot chocolate. We all enjoyed it.
We booked on line and the price was good (I think 57 euros for 2 bedroom).
I recommend the hotel for a simple clean place to stay and would stay there again. \
It is tricky to find (as stated below).

Located near the airport. Available free parking with video surveillance. Hotel decorated in Turkish style. Support nice. Rooms clean but very worn. The hotel is spacious. The price includes breakfast. Unfortunately, breakfast very average in the Turkish style. Everything compensates a good price, I paid 49 €. Nearby are good restaurants in which to eat. I recommend a short stay

Finding ourselves unintentionally in Frankfurt for a couple of days thanks to a pesky Icelandic volcano, we ended up staying at the Hotel Global. Since we weren't planning to visit Germany in the first place, we mainly wanted a clean place to sleep that was cheap and didn't smell like smoke. This little hotel fit the bill. They have one smoking floor and at least two non-smoking floors. The room was rather small but comfortable. Nothing fancy about the furnishings (and it was disappointing to have separate twin beds rather than one big bed), but what was provided was in good condition. The bathroom had a shower stall rather than a bathtub, which was fine by us. Everything was clean and in order.

The locks on the doors use a weird magnetic key card system that we'd never seen before and that was initially a source of some frustration. Opening the door was a three-step process of pushing a button, holding the card to the doorknob, and finally turning the doorknob. Our doorknob turned in both directions but only really worked in one. Maybe this kind of thing is more common in Europe, but it really threw us off.

We paid for breakfast with our stay, which was served in the hotel's restaurant next door. Breakfast is served buffet-style and was acceptable but not incredible. The offerings included more typical European breakfast food such as cereal, bread, cheese, eggs, and fruit, as well as (for us) more unusual fare such as french fries and Turkish-style vegetables. The hotel appears to be run by Turkish immigrants, which I suppose explains the compass rose mounted on the ceiling of our room indicating the direction to Mecca.

The hotel offers free Wi-Fi internet, which worked fine for us, including for a Skype call with one-way video to our kids in the US.

The hotel is located in the Walldorf part of Mörfelden-Walldorf, a pleasant, quiet community that felt very safe. From the airport, the easiest way to get there is by bus; take line 751 or 752 to the stop labelled "Walldorf Am Wildzaun" (cost is 2.40 € for a one-way ticket). The buses are quite frequent during normal business hours and run until late at night. You can also get there by train; the hotel is about a 10-minute walk from the Mörfelden-Walldorf station.

The address of the hotel is on Nordenstrasse, but the hotel is actually located on a little road running between Nordenstrasse and Am Wildzaun. From Nordenstrasse the hotel is not hard to find, and once you know where the hotel is, Am Wildzaun will take you straight to the bus stop.

If we're ever in Frankfurt again, we'd consider staying at the Hotel Global again. If you are looking for something basic, inexpensive, and not located in a red-light district, this is a good option.