[dust2dust]

christmas eve my ps2 did same thing
all i did was get cd/dvd head cleaner
its dvd disk with little brushes on it
there is one thats made by blaze that ps2 thinks is a ps1 game
if its a general dvd claener ps2 wont recognise it(it happened to me) just keep telling ps2 to try read disk again
its all that was wrong with mine worked fine since
if not get a pro to adjust your dvd pot
if this still not work u can buy new laser £30-£50