The original name of the Mahabharata is Mahabharata.
Yes, Mahabharata is a true story.
There are number of heroic things that Arjuna do in Mahabharata. The list is long and beyond the scope. Better you read the Mahabharata. Rather study the Mahabharata.
Ajaamila is personality who comes in Srimadbhagavata, not in Mahabharata
One highly recommended Mahabharata translation is "The Mahabharata: A Modern Rendering" by Ramesh Menon.
sonnet
Sonnet 18 and sonnet 116
The gambling game is what Mahabharata is famous about.
It was Bhimsen who killed Jarasandha in Mahabharata.
It is also called the English sonnet. The other form is the Italian sonnet, or petrarchan sonnet.
Because mahabharata includes in religios discussions
Lord Ganesha wrote Mahabharata and Ved Vyas dictated it.