If you want to disable all comment ratings and the filter on a global basis simply check the box under Settings > General and then Disable all ratings.
Disable Per Review
You can also disable ratings on a per post basis as well. In the right column when editing a single post there is a checkbox titled Disable ratings on this post.
Disable Filter Only
To disable the amazon style rating filter, it can be done with one click in the settings as well. Check the box: Remove rating filter to do so. This is done on a global basis.