MineCraft keeps crashing when I go on single player and multiplayer servers?

So I got a program that cleans junk and stuff off your PC and as soon as I got some stuff cleared and opened MC I go onto a single player world, went AFK (away from keyboard), and it crashed as soon as I got back. I tried reopening it and going on multiplayer and it just crashed within five seconds of being there. I used the MC Installer to fix any issues that were going on and it still crashed. Here's the crash report (or whatever it's called) that came up in the launcher when I got onto a multiplayer server:

A fatal error has been detected by the Java Runtime Environment:
#
# EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x2787ca86, pid=15232, tid=12596
#
# JRE version: Java(TM) SE Runtime Environment (8.0_25-b18) (build 1.8.0_25-b18)
# Java VM: Java HotSpot(TM) Client VM (25.25-b02 mixed mode windows-x86 )
# Problematic frame:
# C [ig7icd32.dll+0x5ca86]
#
# Failed to write core dump. Minidumps are not enabled by default on client versions of Windows
#
# An error report file with more information is saved as:
# C:\Users\Alley Cat\AppData\Roaming\.minecraft\hs_err_pi…
#
# If you would like to submit a bug report, please visit:
# http://bugreport.sun.com/.../crash.jsp
# The crash happened outside the Java Virtual Machine in native code.
# See problematic frame for where to report the bug.
#
AL lib: (EE) alc_cleanup: 1 device not closed
Java HotSpot(TM) Client VM warning: Using incremental CMS is deprecated and will likely be removed in a future release

Force reinstall minecraft and it'll replace the system files.