Apple icons & applications won't load or open

Hi, My 'App Store', 'Viewer', 'Calendar and some others, won't open. They just bounce on the baseline and do nothing. Ive seen this problem on the forum before but can't find it. Anyone any suggestions? many thanks

Restart?

No, too obvious & simple I'm afraid. Unfortunately Apple doesn't do simple!!

What is "viewer"? Never heard of it.

Try this:

Restart the machine and hold the SHIFT key down. Keep holding it down until you see the words "safe mode" on the login screen. Log in and do a couple of simple things. Then restart normally.

Let us know if that improves things.

Also, since you didn't mention it I'd suggest downloading the free OnyX and using it to repair the disk.

Chas, Thanks for the reply. Firstly, i meant 'Preview', not 'Viewer'.
Unfortunately OnyX never found any problems with the disc nor the SmartStatus of the disc.
I tried to re-load the OS software disc to try and repair it that way, but it wants to completely remove all on my HDD with a brand new install.
Two things,
1. It might be an option and totally forget about reinstalling Mavericks as i believe this may be the problem.
2. If i did that, will the 'Time Machine' put back everything that i have on the Mac that i have at the moment, or does each item/folder have to be restored individually on the Time Machine?

Ive tried to restore the problematic icons with Time Machine, but it tells me... “Preview.app” can’t be modified or deleted because it’s required by OS X.". Which is crazy as its not working properly.