We shall take our evidence from the book, as such. Read below for several of the Hermione/Ron moments.

"At least no one on the Gryffindor team had to buy their way in," said Hermione sharply. "They got in on pure talent."
The smug look on Malfoy's face flickered.
"No one asked your opinion, you filthy little Mudblood," he spat. Harry knew at once that Malfoy had said something really bad because there was an instant uproar at his words. Flint had to dive in front of Malfoy to stop Fred and George jumping on him, Alicia shrieked, "How dare you!", and Ron plunged out his wand, yelling, "You'll pay for that one, Malfoy!" and pointed it furiously under Flint's arm at Malfoy's face.
A loud bang echoed around the stadium and a jet of green light shot out of the wrong end of Ron's wand, hitting him in the stomach and sending him reeling backward onto the grass.
"Ron! Ron! Are you all right?" squealed Hermione.
Ron opened his mouth to speak, but no words came out. Instead he gave an almight belch and several slugs dribbled out of his mouth onto his lap.
-CoS, page 112

"He's mad!" said Harry, staring at Krum's dark head as it bobbed out into the middle of the lake. "It must be freezing, it's January!"
"It's a lot colder where he comes from," said Hermione. "I suppose it feels quite warm to him."
"Yeah, but there's still the giant squid," said Ron. He didn't sound anxious- if anything, he sounded hopeful. Hermione noticed his tone of voice and frowned.
"He's really nice, you know," she said. "He's not at all like you'd think, coming from Durmstrang. He likes it much better here, he told me."
Ron said nothing. He hadn't mentioned Viktor Krum since the ball, but Harry had found a miniature arm under his bed on Boxing Day, which looked very much as though it had been snapped off a small model figure wearing Bulgarian Quidditch robes.
-GoF, page 444

Krum had come to say good-bye to Hermione.
"Could I have a vord?" he asked her.
"Oh...yes...all right," said Hermione, looking slightly flustered, and following Krum through the crowd and out of sight.
"You'd better hurry up!" Ron called loudly after her. "The carriages'll be here in a minute!"
He let Harry keep watch for the carriages, however, and spent the next few minutes craning his neck over the crowd to try and see what Krum and Hermione might be up to. They returned quite soon. Ron stared at Hermione, but her face was quite impassive.
-GoF, page 725

Harry climbed into the common room and found Ron and Hermione having a blazing row. Standing ten feet apart, they were bellowing at each other, each scarlet in the face.
"Well, if you don't like it, you know what the solution is, don't you?" yelled Hermione; her hair was coming down out of its elegant bun now, and her face was screwed up in anger.
"Oh yeah?" Ron yelled back. "What's that?"
"Next time there's a ball, ask me before someone else does, and not as a last resort!"
Ron mouthed soundlessly like a goldfish out of water as Hermione turned on her heel and stormed up the girls' staircase to bed. Ron turned to look at Harry.
"Well," he spluttered, looking thunderstruck," well -- that just proves -- completely missed the point --"
Harry didn't say anything. He liked being back on speaking terms with Ron too much to speak his mind right now -- but he somehow thought that Hermione had gotten the point much better than Ron had.
-GoF, page 432

"I told you!" Ron hissed at Hermione as she stared down at the article. "I told you not to annoy Rita Skeeter! She's made you out to be some sort of- of scarlet woman!"
Hermione stopped looking astonished and snorted with laughter. "Scarlet woman?" she repeated, shaking with suppressed giggles as she looked around at Ron.
"It's what my mum calls them," Ron muttered, his ears going red.

"There's something funny though," said Hermione ten minutes later, holding her pestle suspended over a bowl of scarab beetles. "How Rita Skeeter have known...?"
"Known what?" said Ron quickly. "You haven't been mixing up Love Potions, have you?"
"Don't be stupid," Hermione snapped, starting to pound up her beetles again. "No, it's just...how did she know Viktor asked me to visit him over the summer?"
Hermione blushed scarlet as she said this and determinedly avoided Ron's eyes. "What?" said Ron, dropping his pestle with a loud clunk.
"He asked me right after he'd pulled me out of the lake," Hermione muttered. "After he'd gotten rid of his shark's head. Madam Pomfrey gave us both blankets and then he sort of pulled me away from the judges so they wouldn't hear, and he said, if I wasn't doing anything over the summer, would I like to-"
"And what did you say?" said Ron, who had picked up his pestle and was grinding it on the desk, a good six inches from his bowl, because he was looking at Hermione.
"And he did say he'd never felt the same way about anybody else," Hermione went on, going so red now that Harry could almost feel the heat coming from her, "but how could Rita Skeeter have heard him? She wasn't there...or was she? Maybe she has got an Invisibility Cloak; maybe she sneaked onto the grounds to watch the second task..."
"And what did you say?" Ron repeated, pounding his pestle down so hard that it dented the desk.