Programs don't work after a computer issue

[alzza]

I left my computer on for a while and it went into power saving/sleep mode. I thought it was actually turned off so i turned it on but then it made repeated short beeping noises. I then turned it off from the plug then back on. Now with the computer running normally, i try to open up some of my regular programs such as Windows Live Messenger, Google Chrome and Steam but there are errors when opening them up. Some other programs are working fine such as skype and uTorrent.
When i try to open Chrome, it says "Google Chrome has stopped working" immidiately. It doesn't even give a flash of the interface. It goes directly to Google Chrome has stopped working.
With Steam it says "There was a problem with your Steam installation. Please reinstall steam".
Windows Live Messenger says "The application was unable to start correctly (0xc000007b). Click OK to close the application. Same with Chrome, it goes directly to the Error box.

In the beginning before i started having the issues, all my programs were working fine.
I tried restarting my computer. System Restore unfortnately has no restore points. Defragged my computer.
Haven't fully tried Error Checking yet because it takes a VERY long time.

Is it most likely that my files are corrupted? If so, is there a program i can use to fix corrupted files before i attempt to use the built in utility Error Check from windows?

Also i need to use Internet Explorer since firefox won't open after i installed it. Help me and save me from Internet Explorer LOL.
Not even sure why Internet Explorer works :/

Just opened iTunes and it says "iTunes was not installed correctly. Please reinsrall iTunes. Error 7 (Windows error 193)"

 

[The Stealthinator]

How old is your machine? If it, or the hard disk is more than 3-4 years, chances are it could start causing problems. Maybe the Program Files on the disk got corrupted. Have you tried reinstalling the programs that stopped working? See if that works.

 

[alzza]

I have tried repairing and reinstalling the programs but they end up with the same error. Everything with my machine is new, made this year. Except for my hard drive which was made probably about 3-4 years ago.

 

[alzza]

Also when i click on links sent via skype, it says "Couldn't load XPCOM".

 

[The Stealthinator]

I'm not sure. See if a program like CCleaner can get rid of the programs. If not, try download the EXE of the program and running the install again. You might wanna check that all the Program Files are there. Run a disk check in Command Prompt to make sure your hard disk has no errors.

 

[alzza]

CCleaner doesnt work, and most EXEs can not work, after a reinstallation it still does not work.

 

[The Stealthinator]

Then the only thing I can say is run a disk check to see if your hard disk is bad because that might be what is corrupting the files. You could also try de-fragmenting it.