1. For remove the website input you can check this thread http://support.jegtheme.com/forums/topic/move-comment-form-and-remove-website-field/#post-29876 then refer into point 2.
2. Can i disable all plugins except required plugin that related to JNews on your website? Maybe there’s plugin conflict issue in there.
4. For captcha did you use a plugin? If yes, have you try to contact the plugin author regarding the issue?
5. For post time, you just need to change the date format. You can check here about post date format https://codex.wordpress.org/Formatting_Date_and_Time. May i know which post date that you want to change (single post, or module element)?