Is this the correct explanation of the difference between "excited" and "exciting", "bored" and "boring", etc?

The Original Poster's explanation is fairly accurate. Here is a more in depth account:

Agents and patients

In the sentence:

• Bob punched me.

Bob is the person doing the action. In grammar, we say that Bob is the AGENT of the punching action. Me, the person receiving the punches, I'm the PATIENT. I am the recipient of the punching action. Now look at this sentence:

• I was punched by Bob.

The grammar of this sentence is different, but Bob is still the agent, and I am still the patient of this sentence. Bob is doing the action. The action is being done to me.

Adjectives

Now, some adjectives explain how nouns do things, sometimes to other people or things. Here are some examples:

• The DJ played annoying music all night.
• The elephant told us an interesting story.
• Rain supplies life-giving water to the plants in the forest.

Notice that in these examples the music has the effect of annoying people. The story has the property of interesting people. The water has the property of giving life to other things. These -ING adjectives describe potential actions:

• annoying, interesting, giving life

The nouns that these adjectives describe, are the potential AGENTS of the actions. In the phrase

• annoying music

.. the word music describes the agent of the annoying action. ING-adjectives usually describe the AGENTS of the potential action.

However, adjectives ending in -ED are different! This is because ED-adjectives normally describe the PATIENTS of actions.

• The bored students went to sleep.
• The excited monkeys started howling.
• Happy customers are easier to talk to than annoyed customers

In the sentences above, the students didn't bore anybody. Something or somebody bored them. They were the recipients of a boring people action. Similarly, something excited the monkeys. The monkeys didn't excite anybody. In the last sentence, something annoyed the customers. They did not annoy somebody else.

Conclusion

• annoying habit

• exciting news

• *annoyed habit (wrong)

• *excited news (wrong)

ING adjectives describe the AGENTS of actions. But ED ones describe the PATIENTS of actions. Annoyed habit is wrong, because nothing annoyed the habit! Habits don't have feelings, so it is very difficult to annoy habits! In the same way, "news" doesn't have feelings. We can't excite the news! Of course the news can excite people and habits can annoy people. For this reason, exciting news and annoying habits would be correct.

In other words, the Original Poster is correct.

This is frightenING:

This is frightenED

Araucaria's answer is accurate as far as it goes, but I wanted to add a bit more.

Things can be patients of many verbs, like finish, polish, cook, bury, so we say e.g. "unfinished work", "polished stone", "cooked food", "buried treasure".

Participles ending in -ed generally can be used whenever the modified noun would be the object of the verb in a sentence. Sometimes, the object of a verb is the recipient of an action, but not all verbs in English work like this. For example, the Wikipedia article on the concept of Patient mentions that a direct object might instead be what is called a "Theme": something that is not affected by the verb.

It's not as easy to find examples of -ed adjectives from verbs like this, but there are a number of ones starting with the negative prefix un- that are fairly commonly used to modify inanimate nouns: unintended consequences, unsuspected power, unexpected arrival, undoubted truth.