Well, I've read that the Muslims living in al-Andalus were pretty dismissive of the Franks they were in contact with and lived amongst. Regarding sanitation, they were very put-off by their lack of bathing. And they outright refused to learn the Frankish tongue; officials would always bring a translator when dealing with Franks, rather than bother / demean themselves by learning the language (in contrast, the Franks were positively voracious in their stance toward the Islamic culture of the Arabs and Berbers -- they became quite skilled in Arabic, and proceeded through their sciences and philosophy, which would prove quite influential to the Christians. I have heard this contrast between the two cultures' stances toward one another used to partially explain the later rise of Christendom and decline of the Dar-al-Islam)

I know one of the European peoples with whom the Ottoman Empire was in close contact with was the various mercantile city-states of Italy, such as Venice and Florence and Genoa. Perhaps their greatest contact in Christendom was with the Byzantines. So I would venture to guess that their opinions of Europe were largely derived from their contacts with these peoples. And these were some of the most advanced cultures Europe had to offer at the time.

I would imagine that the views of the Seljuks and the Ayyubids toward Europe were largely colored by the Crusades, and so likely quite negative.

I've never heard anything regarding outside opinions of Europe's periodic witch hunts, but much of the Islamic world harbored their own superstitions, such as of the jinn or of the Evil Eye. The latter superstition, especially, has seen much violence done in its name. Therefore, I would imagine that Europe witchhunts -- while obviously excessive -- would have been somewhat understandable.

The term "Dark Ages" is pretty much a problematic term there, unless you're not referring to the Seculum Obscurum.