Indecency with a minor 8 years ago while still 15. Can I get that expunged?

For juvenile cases you don't do an expunction but rather you have your records sealed, Contact a Board Certified Juvenile Law attorney to help you.

What is going to happen to my son, he received a letter of indictment

It means the chances are he was charged with Evading Arrest in a Vehicle which is a felony. He needs to hire an attorney.

Yes the statute of limitation is two years from the date of offense.

Is it possible to get a non disclosure or expungement with a burglary of a building conviction

If you received a conviction your chances of removing the records are slim to none.

Will it go on my record?

For what you said you never received a criminal charge for Theft. Legally you can be sued civilly but it rarely, I never had anyone sued, happens....

If he said you got timed served you probably ended up with a permanent conviction. You need to contact an attorney to See if you can reopen the case.

How long do I have to press charges on an assault to my kids father for coming to my house

Technically 2 years but waiting even a couple of days weakens or may nullify your case.

If it is the same medication in the same dosage you should be fine as long as your pills don't exceed the amount listed on the bottle.

Can a charge that was dismissed in a case still be used in that case to enhance sentencing?

It can't be used to enhanced but it can still be considered in punishment.

Am I eligible for expunge or non disclosure?

No if you did jail time to complete your punishment you are not eligible for either remedy.