Mac not working properly

Question

Safari and Firefox are running very slow and I cannot open iTunes or QuickTime Player after doing the following updates:
Updates:
OS X Update 10.9.3
iTunes 11.2.2
Safari 7.0.4
Digital Camera RAW Compatibility Update 5.05
I get the following messages:
iTunes quit unexpectedly while using the MediaToolbox plug-in.
QuickTime Player quit unexpectedly while using the MediaToolbox plug-in.
or
The last time you opened QuickTime Player, it unexpectedly quit while reopening windows. Do you want to try to reopen its windows again?
I had to install the OS X, iTunes, and Digital Camera updates twice.  The first time I got a message saying one of the updates did not install.  However when I went to redo the update in the App Store all three were ready to update, so I chose update all.
Also, after the first update process finished a message popped up saying the mac was being optimized and performance could be affected, that was over 24 hours ago.
I just noticed the speaker icon on the upper right corner next to the day and time is grayed out.  When I click on it the volume is turned all the way down and I cannot raise the volume.
Thanks in advance for any help you can provide.

Answer 1

Run the combo updater but if you still have problems, I would do a reinstall of OSX using Recovery Drive.
OS X Mavericks 10.9.3 (Update (Combo)
http://support.apple.com/kb/DL1746
Boot into the Recovery Drive by holding down Command R when restarting.
MORE INFO ON WHY RUNNING COMBO FIXES ISSUES
Apple updates available from the Software Update application are incremental updates. Delta updates are also incremental updates and are available from Apple Downloads (software updates are generally smaller than delta updates). The Combo updates contain all incremental updates and will update files that could have become corrupted.
Combo updaters will install on the same version as they're applying--no need to roll back or do a clean install. So if you think you've got a borked 10.8.4 install from a regular update, just run the 10.8.4 Combo Updater on that system.
"Delta" updaters can only take you from one version to the next. For example: 10.9.1 to 10.9.2. If somehow the 10.9.2 is missing something it should have, and that something isn't changed between 10.9.1 and 10.9.2 it will still be stale after the delta update.