A General Suggestion

While working with Kali Linux, if you find Kali Linux freezes occasionally, then follow few steps.

STEP 1: Check if other OS, if installed, is working properly.
STEP 2: If  YES, then check STEP 3 and if NO then check STEP 4
STEP 3: It could be an issue with Kali Linux. Perform below steps to resolve the issue.

• Check for the update if available, if you have internet
• While updating if you find an error, then read the error carefully and accordingly contact for support in forums or else submit your report to https://bugs.kali.org/main_page.php
• Always install the updated version of OS to fix the bug. If there is a bug in the installer, then check this link http://www.kali.org/how-to/tracking-fixing-installer-bugs/.

STEP 4: 

• check HDD if found any bad sectors
• check RAM "clean if needed"
• check if any usb drive is attached
• check power supply and static problems around or in the pc/laptop