Well lets see. Kuh is
Persian for mountain. Hindu Kuh is Persian for Indian mountain, because Hindu is the word used by everyone west of the Indus for Indians, before the British formally partitioned the country into Muslims, Christians and Hindoos [i.e. other unidentifiable stuff that they are not familiar with] around 1829
http://www.etymonline.com/index.php?term=Hindu
Ibn Batuta's travels is the Moroccan Marco Polo who wrote colourful tales of his travels and decided that the Hindu Kush means Hindu Killer, because Indian slaves died there in the cold during transport. His is the only reference that uses this etymology. Not sure how Kush = killer [edit: acc to wiki, apparently old Persian kush = killer, will need to check that]
There is plenty of disinformation in the rest of the saffronised history.
After the Mongols started their trail of destruction in 1205 in China, they progressively moved all the way from both sides through Siberia, Manchuria, Europe, Persia, Mesopotamia, Japan, Vietnam, Java, finally converging in India and meeting up with the Turkic dynasties ruling India at the time [in the form of four successive Delhi sultanates]. Somewhere along the line, probably in Persia, they adopted Islam [at various other times they were Buddhists, Christians and Tengriks]
http://en.wikipedia.org/wiki/Mongol_Empire
The battles were fought between the Mongols and the Mamluks [the Mamluks were descended from Afghan
Ghorids "Indian slaves" who became kings], The Mongols and the
Khiljis [also an Afghan dynasty], the Mongols and the Tughlaqs [the
Tughlaqs were Turkic in origin but allied with the Afghans], which was the war that Timur fought.
Timur weakened the Delhi Sultanate and deputised the
Sayyeds in Delhi. The Sayyeds claimed to be descended from the Prophet [they still do, in India]. They hung around for a few decades, then abdicated in favour of the
Lodhis the final Delhi Sultanate and a Pashtun dynasty.
The Lodhis were finally defeated by Babur who then established himself in India as the first emperor of the Mongol dynasty that was to rule India for the next 800 years. He was the grandfather of Akbar, the Great. By that time the Mongols had become Persianised and Turkicised
http://en.wikipedia.org/wiki/Mughal_Empire
Thats the Hindu holocaust. Muslims fighting Muslims.
Keep in mind that the greatest casualties of the Mongol wars were on the Muslim world. The worst sufferer was Baghdad where every soldier was told to return with two heads and all of them were laid in the center of the city. 20,000 Baghdadis [from the city alone] were massacred. I guess the Iraqis are just lucky like that.
No idea where the other figures in Ulti's link come from, will have to check.