What is the meaning of "Pose'ach Es Yadecha"?
Radak: You give to them food abundantly, to satiation.
Malbim: This corresponds to "Tiftach Yadecha Yisbe'un Tov" (104:28; you give more than needed for satiation).
What is the meaning of "u'Masbi'a l'Chol Chai Ratzon"?
Rashi: He satiates [all beings, with] His goodness, desire and Brachah.
Ibn Ezra: [You satiate all with] what will suffice for them.
Radak: Each receives according to its desire.
Seforno: [You satiate all with] Chen and Chesed, for this is Your desire - "Chafetz Chesed Hu" (Michah 7:18).
Alshich: "Chai" is a Tzadik; "Ratzon" is desire to cling to You.
Yosef Tehilos: You satiate both good people and sinners. You did not withhold from them, even on the day that they made the Egel!
Malbim: The verse depicts that "Ratzon" is an entity that opens Hashem's hands to give abundantly. Then, at a time of Ratzon, every being receives extra satiation.
Michtav me'Eliyahu (1, p.17): A Tzadik wants to receive the reward for his Mitzvos in the world to come, and his punishment in this world; a Rasha wants oppositely. Hashem fulfills the desire of both of them!
Michtav me'Eliyahu (1, p.17) #2: One truly enjoys only what he yearned to attain. This is why people complained "Zacharnu Es ha'Dagah Asher Nochel b'Egypt Chinam; v'Atah Nafshenu Yaveshah Ein Kol Bilti El ha'Man Einenu" (Bamidbar 11:5-6). They could taste anything in the manna, but because it came without any efforts, Le'umas 1 the free fish in Egypt, it did not satisfy them.
I.e. this is like (reminds us of) the fish, which were given for free. Or, as opposed to the fish, which we toiled to catch (even though they were free), we get the manna without any toil. Midrashim say that Resha'im needed to go far to collect it, and "Asher Tofu Efu v'Es Asher Tevashelu" (Shemos 16:23), "v'Tachanu va'Rechayim Oh Dachu ba'Meduchah" (Bamidbar 11:8)! We cannot say that Tzadikim complained! (PF)
