Long story short we had him served with a notice that told him he has to be out within a certain period (24-48hrs or something like that)
Depending on how long he's been the roommate that would be insufficient notice. Most states would consider him a tenant after 30 days, which would require a 30 day notice.
So my uncle, grandfather and cousin show up and we go down to the basement to tell Ron politely and as civil as possible(with permission from Mark), you're going today bud.
Wrong way to handle it. I can see 3 situations this could result in:
Ron has established tenancy. You are illegally evicting him. If he calls the police, you can face huge fines. In that case you would have to serve him the 30 day notice (or whatever the law in your state says) and take him to court if he has not moved out after that. After the court date you would get a court order and your local LEO would have to execute the order.
Ron has signed a lease/similar document. In that case Mark would have to follow the lease (including notice periods etc.). Some provisions in the lease, esp. shortening notice periods, could be invalid. And if the lease is for a certain duration, like 1 year, Ron would probably be allowed to stay there for 1 year.
Ron is basically a long term guest and has not established tenancy. In that case you would not be allowed to throw him out, because Mark can have anyone as a guest he wants (unless specified otherwise in the lease). If Mark wants Ron out, he can tell Ron. And if Ron doesn't leave, Mark can call the police because Ron is trespassing.
Well my grandfather, 72years old at the time, fucked up back and all, took a swing at Ron because this is his daughter that this guy is threatening.
I don't think I have to explain why this is stupid, right?
So at this point Ron, being the good law abiding citizen he is, decides he's going to call the cops and use them against us.
To be honest, I can understand why. You are (potentially) trying to illegally evict him and your grandfather has tried to punch him. Ron is an Asshole, but that does not mean that he has no rights.