1)
Why will he lift his hands?
1.
Radak: I will accustom them and my heart to do the Mitzvos, and I will accustom my mouth to speak about them.
2.
Malbim: I lift them to do Mitzvos "Asher Ahavti", and not amidst hope for reward.
2)
Why does it say "v'Asichah v'Chukecha"?
1.
Malbim: I speak in Your Chukim, even though their reason is hidden from me.