Why does the Torah insert this Pasuk here?
Rashi: To point out that, although Hashem owns the whole of heaven and earth, He desired the Avos out of all the creation, and chose their offspring Yisrael to be His.
What is the difference between "Shamayim and "Shemei ha'Shamayim"?
Ramban: "Shamayim" refers to the celestial bodies - the angels, the sun, moon and stars; 1 "Shemei ha'Shamayim" to the four basic components, which come from the power of the heavens 2 from which everything in this world is formed.
Chagigah, 22b: They refer to two heavens (One is space, the other, the actual heavens - Maharsha). 3
Ramban: See Tehilim, 148:1-4.
Ramban: Just as the Torah writes here "ha'Aretz ve'Chol asher bah".
Perhaps that is the meaning of what we say every morning in Birchos ha'Shachar 'Atah Hu Hashem Elokim ba'Shamayim u'vi'Shemei ha'Shamayim ha'Elyonim'.