If you no longer need the OMNIC software, you can safely remove it from your computer using its uninstaller or Add or Remove Programs feature:
If you use Windows XP or below you can go to Start > Control Panel > Add or Remove Programs. In the Currently installed programs box, click on the OMNIC program and then click Remove.
If you have Windows Vista or above you need to go to Start > Control Panel > Programs > Programs and Features. Select the OMNIC application and click on Uninstall.
After that, try running AdwCleaner to make sure that there are no leftover rogue registry keys or toolbars in your system.