PopCap has probably already made ten times what it cost them to build Peggle. This means that, while they wouldn't turn it down, they don't need your money. Considering however that Peggle is pretty much universally liked (though notably not 'beloved'), you can bet that it's worth checking out.
Peggle has more agency than Pachinko, but less than Pinball. Players shoot a ball from the top of the screen, bouncing it off pegs and blocks, trying to collide it with all the orange pegs before they run out of shots. However, pegs and blocks disappear whenever they are hit by the player's ball, meaning that options get fewer and choices get harder as the game wears on. Making everything harder is fact that no human being could possibly predict how a ball is going to bounce past the first two ricochets, which makes whether you win or lose pretty random in the grand scheme of things.
This is absolutely on purpose. Whenever you lose it's always just bad luck, can't be helped, and maybe you'll be luckier next time. However, when you hit that final peg, and Beethoven's Ode to Joy begins to play and your ball smears rainbows across the screen and the words "EXTREME FEVER" flash over the stage, you know that you can pat yourself on the back because that was all you. There's no denying that Peggle is fun and if that's what you're looking for in a game then there's no need to read the rest of this review.
But what if you don't care if games are fun or not?
What's not often mentioned about Peggle is that it is bizarre. Upon starting the game you are greeted by a unicorn, who serves as your first "teacher" in "story" mode. This mythological beast is followed by not-so-mythological beast from a fast-talking rodent to a Buddhist owl, and at least one plant. There doesn't seem to be any rhyme or reason to the selection of characters, and each has a power that they can grant you that doesn't seem particularly connected to their personality. The Buddhist owl for instance will give you a power that can automatically pick the best angle for a particular shot, affirming its selection by informing you that it has, say, "230% more Zen" than the shot that you chose.
In another game this randomness might smack of catch-all marketing ploys not being thought through, which may be what it is, but in practice it comes across as a strange free-association collage where the elements of the game are meant to be so weird that the player stops wondering about their meaning and concentrates only on their function. Oddly enough this puts Peggle in same genus as the early Super Mario games.
My game design professor once told my class a story about an experiment conducted by behavioral psychologists. They took two mice and placed them in separate cages. In one cage was a lever that would dispense food whenever it was pulled. The mouse in this cage would sleep, clean himself, etc. and pull the lever whenever it became hungry. However, the other cage had a lever that would randomly dispense food upon being pulled. The mouse in this cage did nothing but pull the lever, over and over again, until it passed out. Upon waking, it would return to pulling the lever, endlessly. This is called an 'intermittent reward schedule', and is why some people find slot machine so compelling. The moral of the story is that the problem of how to design an addictive game has been solved, but "what self-respecting game designer wants to design slot machines?"
It is the slight mechanical shift that keeps Peggle from being nothing but a slot machine, but it is the brilliant bizarreness of the game's theme, that is at once a parody of casual games and well as being a pitch perfect embodiment, which makes it a game worth playing for more than simply having your pleasure centers massaged.