The List
There are 75 5 letter words with Q as the first letter. The highest scoring is QUAKY at 21 points in Scrabble, though Words With Friends prefers QUICK at 22. 28 carry three or more vowels, which makes them useful for dumping a vowel-clogged rack.
QADISQAIDSQANATQIBLAQOPHSQORMAQUACKQUADSQUAFFQUAGSQUAILQUAIRQUAISQUAKEQUAKYQUALEQUALMQUANTQUAREQUARKQUARTQUASHQUASIQUASSQUATEQUATSQUAYDQUAYSQUBITQUEANQUEENQUEERQUELLQUEMEQUENAQUERNQUERYQUESTQUEUEQUEYNQUEYSQUICHQUICKQUIDSQUIETQUIFFQUILLQUILTQUINAQUINEQUINOQUINSQUINTQUIPOQUIPSQUIPUQUIREQUIRKQUIRTQUISTQUITEQUITSQUOADQUODSQUOIFQUOINQUOITQUOLLQUONKQUOPSQUOTAQUOTEQUOTHQURSHQUYTE