I messed up the permissions on my box and on restart three quarters of the services would not come up so doing a database backup was out. All my previous DB backups had the plugins still active. So when I tried to restore using them the blog is viewable, but when I try to log in I get a blank page on checking my Apache logs I saw the following error
Cannot use string offset as an array in wp-includes/capabilities.php on line 116
Restored database a couple of times nothing worked, tried upgrading & updating database nothing worked. Finally just installed WP from scratch with blank database. Opened up PhpMyadmin replaced new WP tables with tables from old WP DB backup, skipped table wp_options as it broke the new WP and both user tables as I had already setup the new user data on install, but I guess if you want to keep the old user data you can transfer these too.
Now I just made a backup of wp_options after restoring all the settings e.g blog name etc and turning off all plugins. This way next time all I have to do is just switch this table with the one from a backup whose plugins were still on at backup and am good to go.