If the player is halting halfway through the database refresh, you’ve just located the issue. If the player is having a hard time parsing a file for access on the device, this is where it will freeze. There’s a file with album art that’s too large, or the wrong format. All you need is a straightforward jpg file of 500x500 or less, under 100kb in size. It’s only going to be displayed on a little screen.
iTunes media is optimized for one family of devices, the iPod. If anything else is used, Apple could really care less. You have to be smarter than that little machine, as it’s only a humble few grams of electronics. Thankfully, correcting your iTunes media is relatively simple, and once it’s done with any one of the many available tools to fix them, the media should play on anything else. You only have to fix your music once.
On a personal computer, we have a multitude of tools and a much larger processing environment to work with. This is why the iTunes files seemto play without incident on your computer. On any portable device, the machine is trying to perform a simple playback task. It can’t correct glitches like a desktop PC can. My daughters received a few 'Pods as gifts, they all reverted back to the familiar interface and better sound of their Clips. I spent hours restarting the little anodized aluminum things when they’d freeze too.
Don’t take a mountain of media and expect it to work all in one go. Transfers take but a few moments, it’s much better to transfer a few albums at a time, and enjoy the music.
Even a little Ipod isn’t perfect, just try working with one of the earlier generations of the Shuffle. I especially enjoyed remembering how to tap out Morse Code on the little middle-of-the-cable remote on the teeniest one, I felt as happy as a little boy, remembering the countless hours as a Cub Scout tapping out the Morse code, just to find the next song.
Sorry you’ve had issues with the little machine. They’re tough little guys, once set up properly, they march on just fine.