my media players won't play my dvd's?

[Ernest R]

windows 7 64 bit os-have had no problems with dvd playback using wmp, zoom pro media player until now.all of sudden i'am getting- this disc is not formatted to play in this region-on both media players.never had this issue before.funny thing is that vlc plays the dvds.i'm using lg led le5300 tv through hdmi on my amd 5770 video card.was working with this display so maybe tv not issue.before tv i was using dell 2408wfp-also checked with dell connected and did not play.now again never had issue with dvd playback until two days ago.video card driver is up to date.could it be my lg dvd drive(but it does play using vlc player and it does play media discs on any player)the dvds i have been trying to play are from north american region-avatar, resident evil, star wars new hope, etc.some advice would be appreciated