There is one main differences between Moodle & OpenElms, and they feeds all the other differences:
OpenElms has been built to serve the elearning needs of business, as opposed to Moodle which is designed around formal education (primary, secondary, further and higher).
This means that:
a) OpenElms is built in asp. ie. it only runs on Microsoft servers
b) OpenElms is primarily focussed on delivering and tracking SCORM content packages. I don't think you'll the interactive features in Moodle like forums, wikis, assignments, glossaries.
If all you want to do is deliver and track SCORM packages (please see my post "SCORM warning" before you decide), and you work in a place where Microsoft is the only platform allowed, then OpenElms may be a good solution. In that scenario then Moodle definitely would be the wrong the solution. In particular SCORM was definitely not at the top of the priority list in its design - and rightly so, as SCORM is irrelevant for its target audience.
OpenElms is not as easy to try out as Moodle, as you need to find a friendly Windows Server administrator first. But it's worth looking at.