So very sorry to hear about the errors you're seeing and if you lost any content from uninstalling :( Those of you who missed our warning, WordPress does a good job cleaning up when you select to remove a plugin, unfortunately we have no control over their clean up process which removes everything associated with the plugin when uninstalling. In the future, we strongly recommend backing up your entire site (MySQL database + server files) before making any major changes (i.e. installing something new or removing something big!)
Those of you who are seeing blank options and fatal errors, would you mind sending as much detail as you can through our bug report form here: http://www.nextgen-gallery.com/report-bug/ including login credentials to your site? PLEASE do not post your login details in the forum here, only through the bug report form!
If you also wouldn't mind temporarily deactivating all plugins (including NextGEN Gallery) and then re-activating NextGEN Gallery only > clear browser cache and reload your site. Does that help resolve the issue you're seeing? If not, while all plugins except NextGEN are deactivated, temporarily switch to a WordPress default theme (i.e. Twenty Twelve), does that work? Just trying to see if there are any plugin or theme incompatibilities.
For those experiencing Fatal Errors, if you were to contact your server host tech support and request that the memory in your installed php.ini file be increased to 250MB, does that help resolve the fatal error you're seeing?
If the above suggestions do not help, please submit your bug reports through this form - these reports go straight to our developers to help find a solution asap! http://www.nextgen-gallery.com/report-bug/