I DO have my gun put away! The game said so, and so I do. I am literally being killed by guards because bad guys are killing me. Go on. Form some logic from that. I dare you.

You did do something wrong. You provoked one of the upstanding merchants of the Hub into a fight, and the cops are doing their job, which is to protect the citizens of the Hub. You're just some asshole that wandered in out of the Wastes, so it's open season on you. This is the way the Script is intended to work.
It is possible to blackmail Bob into giving you money, but the risk is getting into a fight, like you did. It is not possible to "turn him in" for using human meat. Some folks think this is an oversight in the quest list, but I'm not sure. I think that it could have been an intentional design decision. It's a tough world, and at the end of the day, the folks of the Hub don't care if "Iquana Bob's is People!" Just as long as it's nobody they know, and some jerk from the Wastes doesn't rub their noses in it.
Easier to shoot the messenger. Maybe Bob will fry him up after...
Just because things went badly for your character, it doesn't mean the game is flawed. The game is meant to have a certain amount of difficulty. There are tons of places where a small slip-up can really ruin your day. That's why the manual says to save often. They're not pulling many punches, so when you get wiped out, you're supposed to grin and bear it and keep trying.
Yes, you are the hero of the story. But it's a rough world, and sometime the good guys get schooled. You can "win" the game, but it's not possible to get a happy ending for everyone in the game.

Here is the logic: You are the bad guy.
Han shot first, but that didn't make him the bad guy. Just because Bob shot first, and just because you think he's bad, doesn't mean the Hub Cops will see it that way.
I know it's hard for you to process this, but if the guards are shooting at you, it's because you did something specific to make them think you are the bad guy. Unfortunately for you, pissing off Bob enough to make him want to shoot at you is one of the things that makes the Hub Cops think you're the bad guy.
Just because you're the player, you're not automatically thought of as the hero by everyone in the game. The way the game is designed, you can walk around the world being an evil bastard. But if you act like a bag of dicks, word gets around and most of the folks in the world won't like you.
But a Laser Gattling Gun means never having to say "I'm Sorry".

Oh my god, the nerd stink is too strong in here. I'm not going to take part in a "Han shot first" debate.

If you wandered out of the casino while still in combat mode, it will trigger the guards outside to come join in, and then your hate spreads far and wide. When I killed inside the casino, I had to kill every last guy and girl, and only then could I quit combat and leave the casino unmolested.

Yeah, Last time I played Fallout 1, I blew the choices, and had to kill the fat guy. Oh well, Atleast he had that nice mouser gun. But all Mayor Macgyver did was get upset because I killed the fat guy instead of the men. They never tried to hurt me.

Well, as much as I know Han shot first....=P jk jk bro. Just hit that magical "new game" button and be sure to have two save game files.
Or....you can forget about Junktown an move on to greener pastures. I mean it's not like you need to visit Junktown to beat the game. So bro, one word of advice when something happens again in fallout: CHILL.
...or just have a minigun with plenty of ammo

The beauty of Fallout is that you -never- have to say you're sorry if you have power armor and enough ammunition! :D

Don't worry if the Junktown guards get hostile, you can continue without trouble.
When I first visited Junktown Killian (when shooting at the assassin) accidentally shot at my party member Ian who killed him in return.
So nearly the whole town became hostile and I had to shoot them.
But wiping out nearly the whole town didn't have very negative consequences for the game, I got fighting XP and loot instead of quests in Junktown and still could become the hero in the rest of the world.
Freedom is a great thing about Fallout: You can help the good guys, you can help the evil guys or you can kill both and loot them.

I think it makes a difference if you collected the evidence before the fight starts. So if you had the bug equipped (or what ever is necessary for it to work) and get the confession from gizmo you wont be jailed.
I killed gizmo, the bodyguard and the two casino guards in my first try and noone else went hostile.
Also I killed alot of gang member by either speaking to aka provoking them in the bar or trying to steal from them (indoor) without being arrested or anyone even noticing it. (including surviving members)

I LOVE this quote : ).
I wish more games were like this..