Have you tried:
– deactivating all plugins to see if this resolves the problem. If this works, re-activate the plugins one by one until you find the problematic plugin(s).
– switching to the Twenty Eleven theme to rule out any theme-specific problems.
– resetting the plugins folder by FTP or PhpMyAdmin. Sometimes, an apparently inactive plugin can still cause problems.
– re-uploading the wp-admin and wp-includes folders from a fresh download of WordPress.
I seen online to re-install the cron.php and teh wp-cron.php, how can those files get corrupted?
It just happens on the best of servers sometimes.
Is that why Blogging platforms like Blogger/WordPress, or online communities have several MB of folders and individual files?
No. WordPress several mb of files because it needs all of them to run. I can’t comment on what Blogger does/doesn’t need.
See also http://wordpress.org/support/topic/scheduling-for-later?replies=5
Please don’t make multiple posts next time.
File corruption, which happens, is why we make backups.