I think your system needs some TLC! Try an Archive and Install:
How to Archive & Install:
and this also:
I do not have an install disc anymore. :-( Lost everything in 'it's a long story category'.
Call Apple Customer Support 1-800-767-2775, provide the Serial Number and specifications of the Mac, and for a reasonable fee, they will supply a replacement set of system discs (if available).
The discs will be for the original version of the OS that was pre-installed when the Mac was manufactured.