Larry may be able to help with the gapless stuff, personally, I couldn't get it to work.
-marko.
Gapless "can" work by default on iPods that support it (older iPods do not), as long as the mp3's were ripped using an encoder that includes the gapless info (like the default MC LAME encoder.)
Note that I say it "can" work -- I say this because there is a bit of a "gotcha" in that if the songs are encoded VBR (which is the standard), you have to let songs play straight through from the beginning in order for them to play back seamlessly. If you pause or seek during a track at all, the iPod gets "confused" about where the song should end and you'll start to hear an error in timing at the seam. The result is not a "gap," but rather a piece of the song is "clipped off" at the end of the track -- i.e. it "skips forward" slightly at the seam. The longer the track, the more of an error you'll potentially hear. On "normal," shorter songs, the result is generally a very small piece of the song missing (much less than a second) which is not always obvious. How noticeable it is depends on what is actually happening at the transition, and whether or not the "skip" is accompanied by a slight "click" which can also sometimes happen. On very long tracks, however, the iPod can potentially clip off a significant piece of the track. I have some hour long tracks, and after pausing/seeking several times during playback I witnessed losing a full 10 seconds or so at the end of a track.
The bottom line is that if you want the iPod to play back "truly" gaplessly, you have to let it play straight through from the beginning of the song without pausing or seeking.
Larry