As to the Jabba scene, itself. Yes, it was originally planned, and actually filmed, but the final effects were never done. This is also from the novelization:
The docking-bay entrance to the small saucer-shaped spacecraft was completely ringed by half a dozen men and aliens, of which the former were by half the most grotesque. A great mobile tub of muscle and suet topped by a shaggy scarred skull surveyed the semicircle of armed assassins with satisfaction. Moving forward from the center of the crescent, he shouted toward the ship.
"Come on out, Solo! We've got you surrounded."
"If so, you're facing the wrong way," came a calm voice.
Jabba the Hut jumped—in itself a remarkable sight. His lackeys likewise whirled—to see Han Solo and Chewbacca standing behind them.
"You see, I've been waiting for you, Jabba."
"I expected you would be," the Hut admitted, at once pleased and alarmed by the fact that neither Solo nor the big Wookie appeared to be armed.
"I'm not the type to run," Solo said.
"Run? Run from what?" Jabba countered. The absence of visible weapons bothered Jabba more than he cared to admit to himself. There was something peculiar here, and it would be better to make no hasty moves until he discovered what was amiss.
"Han, my boy, there are times when you disappoint me. I merely wish to know why you haven't paid me… as you should have long ago. And why did you have to fry poor Greedo like that? After all you and I have been through together."
Solo grinned tightly. "Shove it, Jabba. There isn't enough sentiment in your body to warm an orphaned bacterium. As for Greedo, you sent him to kill me."
"Why, Han," Jabba protested in surprise, "why would I do that? You're the best smuggler in the business. You're too valuable to fry. Greedo was only relaying my natural concern at your delays. He wasn't going to kill you."
"I think he thought he was. Next time don't send one of those hired twerps. If you've got something to say, come see me yourself."
Jabba shook his head and his jowls shook—lazy, fleshy echoes of his mock sorrow. "Han, Han—if only you understand…I just can't make an exception. Where would I be if every pilot who smuggled for me dumped his shipment at the first sign of an Imperial warship? And then simply showed empty pockets when I demanded recompense? It's not good business. I can be generous and forgiving— but not to the point of bankruptcy."
"You know, even I get boarded sometimes, Jabba. Did you think I dumped that spice because I got tired of its smell? I wanted to deliver it as much as you wanted to receive it. I had no choice." Again the sardonic smile. "As you say, I'm too valuable to fry. But I've got a charter now and I can pay you back, plus a little extra. I just need some more time. I can give you a thousand on account, the rest in three weeks."
The gross form seemed to consider, then directed his next words not to Solo but to his hirelings. "Put your blasters away." His gaze and a predatory smile turned to the wary Corellian.
"Han, my boy, I'm only doing this because you're the best and I'll need you again sometime. So, out of the greatness of my soul and a forgiving heart—and for an extra, say, twenty percent—I'll give you a little more time." The voice nearly cracked with restraint. "But this is the last time. If you disappoint me again, if you trample my generosity in your mocking laughter, I'll put a price on your head so large you won't be able to go near a civilized system for the rest of your life, because on every one your name and face will be known to men who'll gladly cut your guts out for one-tenth of what I'll promise them."
"I'm glad we both have my best interests at heart," replied Solo pleasantly as he and Chewbacca started past the staring eyes of the Hut's hired guns. "Don't worry, Jabba, I'll pay you. But not because you threaten me. I'll pay you because…it's my pleasure."