It could be grounds for an appeal or collateral attack. Speak to a local defense lawyer and provide all the facts.

Why did i get a summoning letter to court for eviction ?

I assume you got the letter because the landlord claims differently. So go to court and fight it.

Can I sue and become owner of a apartment?

If the property is in the UK, contact a local solicitor. If it is in the US you will need to contact a local real estate attorney and have them...

Can I get a Wal-Mart banned taking off for my son and I?

As long as they are not discriminating against you based on race, age, gender, etc., it is permissible for them to issue you a no trespass.

Ok?

It would be improper for his lawyer to discuss this with you.

Lawsuits are based on damages and based on what you have described you don't have any.

As noted, the police can pull you over for an improperly registered vehicle.

What type of attorney would i need to contact in regards to being a consumer and experiencing discrimination ?

It is perfectly legal to discriminate based on tattoos, if that is what happened.

Can I sue for employees physically harassing me while holding a child?

Unless you or the child suffered an injury, you have no grounds for a lawsuit.

Do I have a case against McDonald's?

If you took one bite, it is unlikely it made you ill. If you continued to eat it after you realized it was raw, that's on you. General rule: No...