How does a person inherit this genetic disorder? Is it dominant or recessive? Is it genetic or chromosomal?

Usually with males, they inherit an X from their mothers and Y from their fathers. With kliensfelter syndrome, the males inherit an extra X making it XXY. Which is typically caused by nondisjunction, the failure of homologous chromosomes to seperate properly during meiosis.

It is recessive and a chromosomal disorder.

http://learn.genetics.utah.edu/content/disorders/whataregd/klinefelter/images/kleinfelter_karyotype.jpg