Best options to choose so i can improve my GPA without any legal issues

Recommend that you speak with your schools designated school official. If you are seeking employment outside of OPT speak to an immigration attorney.

What are the best options to continue my visa status?

You should speak with your DSO if you are continuing in school. If not and you have an employer, H-1B may be available for filing in the beginning...

Can the application for a visitor visa adversely affect an ongoing green card filing? (for the spouse of a green card holder)

As long as there are no misrepresentations an application for a visitor visa even if denied has no affect on the resident status application.

I-130 for parents living abroad

You will need to file a separate petition for each parent.

Yes your attorney may file for you. It may not be faster to ask for just the receipt number. Without the receipt number CIS may not locate the...

You should speak with your DSO about maintaining your F status or having restored in the event TPS expires. You may attend school, work and travel...

What does request for discovery, request for bill of particulars and notice of intention to use evidence mean from defense att?

This is not an immigration question. Recommend you repost on a thread that handles domestic relations.

How long does it usually take to get a decision after (joint) I751 interview?

A few weeks to several months or more.

The two year home resident requirement remains until it is either fulfilled or waived.

New Legal Permanent Resident Insurance options?

Not an immigration question. Contact an insurance agent.