Mediation is also confidential. Nothing said in mediation may be used against a person. Many times people tell me they agreed to something in mediation because they were afraid they might be seen as unreasonable. This should not be a concern in mediation, because of the confidentiality rule. (Outside of mediation, your lawyer can advise you as to what positions are reasonable or unreasonable).
A question is often asked as to whether there is an advantage to being a petitioner versus a respondent. There is no real difference, except that the petitioner can obviously effect when the action is started, and sometimes, in what county. If you and your spouse separate, and your spouse moves to a different county before the action is commenced, the petitioning spouse can commence the action either in the county you reside in or the new county they have moved to. There are some perceived and actual differences as to how matters proceed, depending on which county they are "venued" (commenced) in. A second implication of being a petitioner versus a respondent is that ultimately, if the matter does proceed to trial, the petitioner is required to present his/her case first. This may have some minor implications relative to the cost of preparing for trial, especially it the matter settles before the respondent presents her/his case.
A Motion is a paper asking the Judge or Referee to decide an issue in a case. In a divorce matter, a Motion for Temporary Relief allows you to ask the court to issue a temporary order for child custody, child support, spousal support, and certain property issues. The Temporary Order allows you to get needed financial support while your case is pending in court. The Temporary order will expire when the final divorce decree is signed by the Judge and "entered" by court administration.