Video Poker table

Holding both pairs (QQ and KK) and drawing one card yields a full house on any of the 4 remaining queens/kings and two pair otherwise, giving EV ~12.98 credits, far above holding a single pair (~6.5) or standing pat (10).

Holding the pair of Aces is the optimal play: it already pays as Jacks or Better and gives the best chance to improve to two pair, trips, a full house, or four of a kind. The other cards are unsuited and disconnected, so they add no meaningful draw value.

Holding the low pair of 3s maximizes expected value in 9/6 Jacks or Better; it provides the best chances to improve to three of a kind, two pair, a full house, or four of a kind, and outperforms holding the lone Ace or any 3-card combination.

Holding the low pair of 4s maximizes expected value here; no flush or straight draw is stronger, and keeping a kicker reduces the chance to improve to trips or better.

Holding the pair of queens gives a guaranteed paying jacks-or-better hand and the best chance to improve to two pair, trips, or a full house. The other cards are unsuited and disconnected, so discarding them is optimal.

Holding the pair of Queens maximizes expected value: it already pays as jacks or better and can improve to two pair, trips, full house, or four of a kind. The alternative 4-card straight draw has lower EV.

The dealt hand has no paying pair, no high cards, and no useful flush or straight draw, so discarding all five maximizes expected value.

Holding both pairs (6s and 7s) maximizes expected value: drawing one card can complete a full house, while the current two pair already pays 10 credits.