Hi,
Have a look at the summary here: http://assure.ly/etkFNU. It highlights the features that are either available OR not, depending on what the user has (Acrobat or Reader) and whether the form was Reader Enabled (using Acrobat or the full LC Reader Extensions ES component):
If your users have Reader, then yes you will need to Reader Enable the form using the Reader Extensions component of LC Enterprise Suite.
Good luck,
Niall