In answer to your questions:
1. The featured ads slider, sponsored ads, and social options can all be disabled by settings within the ClassiPress admin dashboard. The custom forms and fields functionality would allow you to leave out the requirement for tags in ad listing pages, and widgets are configurable by you in terms of what you'd like to appear in the sidebar.
2. Not sure which menus you refer to specifically?
3. Yes, ClassiPress has a custom form and fields feature which allows you to make custom forms for ad listings
4. Yes, this is determined by you
5. The content of the ad page can be determined by the custom form you create, thus that is what displays on the page.
6. There is no reCaptcha for the ad listing itself, but you can set this up for registrations to prevent spammers.
7. Yes, there are built in ad spaces, or you can customize additional ad spots of make use of
advertising plugins available in the AppThemes marketplace for ClassiPress. Thanks.