1) Many pet owners share observations of how some music calms or disturbs their reptile pets. So it seems that yes, some animals respond to it. There are many forums where you can find testimonies about this. The scientific validity of these observations is not guaranteed, though.
2) Yes, in some cases. But to have a better understanding of what supposes music for many animals, we should step out from our anthropocentric concept of music.
I find this answer more difficult to explain, in spite of this what I really think. So, give me a try:
I have reading some material regarding this question for some time since you posed it. What I had in mind was that there are many animals that produce different kind of rythmic sounds for some different reasons. Cicadas and crikets males use them to attract females. Male crocs shake the waters in a very charactristic way when mating season, and the interesting thing here is that other crocs are sensible not only to the visual display but to the sound produced. Also, surprinsingly, males crocs make calls during this mating season. Frogs tend to make choirs of calls in given moments of the day. Some lizard owners like to share videos of their pogonas purring, like this one (and I dn't know wether the critter is enjoying the petting season, but it seems so):
So there is an appalling bunch of evidence that animals (other than birds and mammals) use and enjoy rythmic sounds. And as I found out, I was not the first one to notice it.
There is a new discipline called zoomusicology that is the study of the music of non-human animals or rather the musical aspects of sound pr communication produced and received by animals. To my understanding this discipline is in its very begginings and has failed so far to produce a good definition of what is music generated by animals. However there are very interesting new views arising from it, like the reflexion of David Teie that all the music human made is directed to the specific hearing abilities of humans, and hence music directed to animals should be writing taking into account their particular characteristics. The results of one study, led by Charles T. Snowdon, indicate that the species-specific music written by Teie was the first music that was shown to be effective for any species other than human in a controlled study. The most provocative implication of this research is that animals respond to human music in remarkably human ways. Or, more accurately, that there is something about musical stimulation that is so universal as to include beings beyond the human.
It is important to remark that the interest of the effects of music in animals started well before our time:
's Treatise on the Influence of Melodies on the Souls of Animals in the 11th century was the earliest treatise dealing with the effects of music on animals. In the treatise, he demonstrates how a camel's pace could be hastened or retarded with the use of , and shows other examples of how music can affect and , experimenting with horses, birds and reptiles.
As it seems animals sounds have been understimated by our science for a long period of time.