The Wargs were sent by Saruman in an effort to find the Ring before Sauron. Both parties knew that the One Ring remained in existence and had been found by Baggins - a hobbit from the Shire. Saruman was a Wizard-turned-bad via his thirst for power and desire for the One Ring.
wargs
The wargs speak a different language from the spiders and Bilbo.
True
Bilbo and the dwarves are caught first by trolls, then by goblins. they are trapped up in a tree because of goblins and Wargs
You answered your own question. They are called Wargs. They are, in other words, the wild wolves of the mountains.
Wargs. They are slightly larger and can speak.
The wargs were unable to get them out. However, the goblins were able to redirect the fire and were in the process of burning them out.
wargs
Orcs and Wargs. It doesn't say the Wargs kill themselves but they do eat the orcs.
the lord of the eagles, and somewhat gandalf
In "The Hobbit or There and Back Again", the party is traveling through the forest when they hear wolves. They scurry up the surrounding trees and the Wargs rush in. This happens to be their "Meeting Place" with the goblins. The party is trapped in the trees with furious Wargs and Goblins beneath them.
The whole party had to climb up and hide in trees beside the clearing while the wargs came and tried to kill them. Gandalf, who specialises in fire had to burn them to death until the remaining wargs retreated.