A question is made mandatory based on the validation, and this is dependent on the type of question. So when you are designing a question, look below for the validation section. For instance, the multiple choice question lets you control the minimum number of choices the respondent must make.
Reports should be created automatically when you create a survey. If it is not, then something must have run into a problem of some sort. Try to create a new survey - do you see reports under "reports and data" then? It is also possible to create your own report, by selecting "new report" from that same left menu. If you create a new report and make no changes to it, you've got the standard summary report that Opinio creates when you create a survey.