We had to do the same thing in May--arrived P.M. and had A.M. flight out of Frankfurt.

While the Sheraton sounded fabulous, it was too rich for our blood. The NH Hotel Frankfurt Airport was great AND incredibly reasonably priced. They had convenient shuttle service (though the first driver scared the ***p out of me he was driving so fast).

We speak no German, but the staff spoke perfect English.

I highly recommend it and would stay there again.

We stayed at the Moerfelder Strasse 113, Frankfurt, Hesse location (in case there is more than one)