To use these legally, you must into ISO format. Downloading ISOs from the web is piracy.
The game never existed for PSP, so any such file is fake or malicious. For authentic MK9, buy the Komplete Edition on PC or consoles. For PSP emulation, enjoy Mortal Kombat: Unchained – a solid fighter in its own right – but only with your own legal backup. To use these legally, you must into ISO format