Mac OS X crashes often when using Preview,Adobe Photoshop,Pixelmator....

When I work with Preview ,Photoshop,Pixelmator Mac crashes and again reboots. This happens very often like 3 times in 20 minutes.

But sometimes it doesnt happen it works normal for a long period and suddenly crashes.

I happened in Lion OS X so I upgraded to Mountian Lion OS X but still the problem remains

I did Verify Disk then i got

Verifying permissions for “Macintosh HD”

Group differs on “Library/Java”; should be 0; group is 80.

Permissions differ on “Library/Java”; should be drwxr-xr-x ; they are drwxrwxr-x .

Warning: SUID file “System/Library/CoreServices/RemoteManagement/ARDAgent.app/Contents/MacOS/ARDAg ent” has been modified and will not be repaired.

Permissions differ on “System/Library/Frameworks/CoreGraphics.framework/CoreGraphics”; should be lrwxrwxrwx ; they are lrwxr-xr-x .

Permissions differ on “System/Library/Frameworks/CoreGraphics.framework/Resources”; should be lrwxrwxrwx ; they are lrwxr-xr-x .

Permissions differ on “System/Library/Frameworks/CoreGraphics.framework/Versions/Current”; should be lrwxrwxrwx ; they are lrwxr-xr-x .

Permissions verification complete

Please kindly someone me solution or direct to the thread with this problem

Muhil