Use the wysiwyg module and then add ckeditor as a library. It will give you the most flexibility.
You install wysiwyg, then you upload ckeditor into your libraries folder /sites/all/libraries. Then you go to Configuration > Content Authoring > Wysiwyg Profiles and set up your Ckeditor options.
Note: I've read some discussions about Ckeditor changing the format of their internal versioning that causes trouble. I use TinyMCE. I like it better so I don't know much about the trouble people have had with Ckeditor but thaat may be why you can't see it.