I'm probably being thick here, but I'm in a bit of a tangle.

About 2 years ago I got an iPod and recently a second one. As our computer (PC running XP) is only little, I copied iTunes onto our 500-gig external drive and have been happily working in there, creating two libraries, one for each iPod. However, I notice that all the tracks also go into 'My Music' on the C-drive so our poor old computer is filling up anyway.

As an experiment, I deleted a track from My Music and it also disappeared from the relevant library on the external drive.

So, how do I go about sorting this out so I'm only working on the external drive and not filling up the C-drive? Can I move My Music onto the external drive, or will this stop iTunes working? Perhaps I should have moved iTunes there, rather than just copying it.

As I am a fairly clueless old git, answers in words of one sill a bull would be much appreciated, especially if they don't mean losing the contents of my libraries.