Byron,
are you sure your son isnt using Windows Media Player 10 to put the songs on his Lyra? Windows Media player is what RCa recommeds and supports the formats the kyra supports, MP3,WMA, WMA DRM. Itunes would only support the MP3 format. I have a bunch of non apple media players( my job hands them out like candy) and none of them work with itunes. they all however do work fine with windows media player and they also support drag and drop in Windows Explorer. If i was using a non apple device Itunes would be the last software i would use to put music on it, its one of the worst ones out there. Its slow and disorganised , windows media player and Winamp are much better applications for media management.
As far as downloding goes if you buy music from the itunes store you wont be able to play them unless your media player can use AAC(m4a) format unless you convert them to something else. The ipod and Microsoft Zune are the only two i know that can play that format. if you put aac files on a lyra for instance it would not be able to play them.
BTW since Limewire isnt a paid service if you download copyrighted material using it you are breaking the law and people are getting caught all the time.