Answer:
"Donna and I" is the correct form if used as the subject of the sentence (as in "Donna and I went for a walk."). "Donna and me" is used as the object ("She will call Donna and me.).
Check the correctness of the pronoun by eliminating "Donna" and saying just the pronoun with the rest of the sentence. You would not say "Me went for a walk" nor "She will call I."