In my testing Disqus has bugs when using IE 8, I reported them but I don't know if they have fixed it. I recommend IntenseDebate.
Things missing from your skin will not generally cause errors but you may be missing some styles, see the release notes for the 2.3.3.2 release, we added some nicer styles for tables and grids and you should include one of the available options in your style.config, it will make your file manager prettier and Shared Files feature also will look better and other tables and grids in the site management pages.
If you have access to the database, you could run a sql script to enable comments on all pages like UPDATE mp_Pages SET EnableComments = 1
Not sure you would want it on every page but it may be less work to manually uncheck it on the ones where you don't want it than to manually enable it on each recipe page.
Best,
Joe