
The question is: Should you upgrade your existing players? You certainly can, but there's not much added benefit as of now - the players will continue to run just as happily on older Windows versions. Also, Windows 10 will have a lot of updates in the near future, and trigger much extra downloads (important for those of you that use 3G/4G modems), so you might want to stay with the Operating System you have for now.
Edit: It seems now that Windows 10 is being downloaded even if it hasn't been selected in Windows Update, so check your Windows Update settings to ensure you don't get downloads you don't want.