Any time a person violates a term of probation, the judge has the ability to impose the remainder of the suspended sentence. The judge can also impose other sanctions, and can continue the original term of probation. You need to speak with an attorney about your case as soon as possible to discuss your particular circumstances.
First, your boyfriend needs to speak with a good attorney about his case. You can get a person out of jail by "bailing him out," or paying 10% of the bond. Or, his attorney can make a bond argument at his first court date to try to get the bond reduced. Regardless, he needs to speak with an attorney who can help him with his particular circumstances.
If the state cannot meet its burden of proof then the charges will be dealt with either by a dismissal or a not guilty verdict at trial. Whether the state can prove that you were actually in possession of marijuana will depend on the particular facts of your case. You should consult an attorney to discuss your case immediately.
It depends on the court. You should call an attorney and have him or her contact the Clerk of Courts for that jurisdiction. That attorney can help you get the record sealed and inform you of whatever fees are involved. My experience is that there is usually a fee involved when filing to seal a record.
The warrant is likely still active. You need to consult with an attorney who can begin working on your case to try to get the warrant recalled. You don't want this hanging around -- police officers look up people's names during things as routine as traffic stops. If your name were to come back with an outstanding warrant, there is a very good chance that the officer would take you to jail.
You can find the statutes for these types of offenses in Section 2907 of the Ohio Revised Code. They are online at http://codes.ohio.gov/orc/2907.
These types of charges are serious. The defendant needs to consult a lawyer immediately.
Please remember that it is not a good idea to discuss your case on the internet. You should hire a criminal defense attorney tdid insult with in a confidential setting. Speaking generally, whether a person can be sentenced to jail for a failure to reinstate charge depends on that person's history, but a large fine is always on the table. I practice near Stow, you can reach my office at (216) 369-9106 if you would like to discuss your particular case confidentially.