iPods are essentially disposable - the internal, not-designed-for-replacement battery is rechargeable a finite number of times, and that's it. However, my iPod Nano is still going strong after nearly 2 years of daily use, and I go into withdrawal without it. Also, because the modern-generation devices under 16 Gb use flash memory - no moving parts means long run times.
You can play Mp3s gotten from anywhere, or you can "buy" (rent) the tracks from Apple in their locked format. I've never bothered w/ that.
Apple makes you use iTunes to load the music onto the device - and it's horrible quality software. However, the iPod hardware is good enough that I put up with the hassle of iTunes.
Also note that while the uploading happens in iTunes, you needn't do any other functions - Ripping, tagging, organizing, etc. all can be done better by other software, all of which is Free. I like a program called "Exact Audio Copy" to rip my CDs.
I've owned other non-Apple players - a Rio and a samsung; neither were as well-polished as the Apple product.