Limiting moderators

Is there any way that I can either disallow moderators to edit administrator posts or disallow editing posts except for their own?

Nopes, its not possible.

Hm ok, is there anywhere that you can view whenever someone makes a change to a post? Like whenever someone's edited it and stuff.

General>Forum>Security
The administration & moderation tab.

It doesn't show when someone edits a post?

Sorry then if it doesn't its not possible.

At the bottom of each post, if a member has edited the post, then a notification will appear as soon as another post has been added. The notification will display the user that edited the post, and when it the changes occurred. If they put in a "reason" for the edit, that - too - will be displayed.

Take note, however, that this notification only appears when another post has been submitted after the edited post. You can monitor it that way, but as the mods above said, it won't be displayed in the ACP.

In order to stop post edits, you can use the forum permissions and specify which user groups can perform edits.