In windows, and in windows applications, the title or header row allows sorting of the associated info... IF VIEWING IN detailS VIEW.
Simply clicking on any of those titles enables you to re-sort info by that particular category... Name, Artist, Track #, Date, etc. it works in lots of apps like Itunes, My docs, J River Media Center, Fubar, Recycle Bin, Explorer, etc.
If when adding tracks to a play list in Itunes, and suddenly you can no longer move the tracks up or down in it, click onto the very first colum of numbers, 1, 2, 3, etc, until you can again move them about by clicking and dragging once more.