Probs with backed up DVD Games

[frizzle]

G'day,Wondering if someone can help me.Backed up dvd game on Imation DVD-RW and it worked.Backed up with Laser DVD-RW worked last night but would not load the next morning,adjusted the white pot and got it to work.Later on tried to play again did'nt work.Am using the RW's cause my princo DVD's won't work.
I am ready to throw PS2 out of window.My Mod chip is a Magic 3.1 Modchip.