Let me help fill in the missing pieces:
Categories: Configured in the Management Interface by the administrator. Can have as many or as few as you'd like.
Upload Images: Images, video, audio files may all be linked from other sites using the 'Embed Media Content from Various Sites' button on the editor. Uploading new content to the site is not permitted in the Community though.
Ability to close a thread: Threads cannot be locked down, but they do have a status that shows if the issue is resolved or not.
Filter un-answered threads: When viewing the main Community page there are filters for every status and category, including unanswered questions. There is also a reply count on the main Community page that shows how many posts are in a thread.
Switch off voting function: There are role permissions to control who can view or create threads. Those that can view the thread will be allowed to vote on it.
<code> -Tag: The code tag is supported. It is available through the editor, just click on 'more' and look for the code '<>' symbol.
Ban spammers: This is a planned feature for the Community. At the moment, any user may report a thread/post/comment as Spam. If 1 agent or 3 users report it as spam then it is hidden until an agent approves/deletes it.
Request system informations: SmarterTrack includes a feature called Who's On that could be used to view user information on any of the pages, including the Community.
Integrate in Helpdesk: When viewing a Community thread, agents have the option to create a ticket based off the thread.
Multilingual support: There is multilingual support for all permanent text in SmarterTrack. The administrator may install multiple language packs which will provide a language dropdown for users to select their desired language. User created content will not be translated by SmarterTrack. However, we have found that most multi-lingual users will use a browser capable of translating content for them (ie; Chrome) or install an extension that translates content in their browser. You could also add category tags (or regular tags) for different languages that would allow users to filter their result to only include threads with those tags.
Categories: An agent may edit, remove, or add tags to any post. They may also switch its type (ie: question to idea) and adjust its status as well as edit the actual content of the post.
Forgotten feature: Having related Knowledge Base articles and similar Community posts show when viewing a thread and creating a new one can help users find a solution to their issue faster and helps to avoid duplicate posts on the same subject.
Hope that helps clear up some of your questions!