I had the same problem a while ago I was told I had to buy a new laser, but in the end I just bought a new console instead. As far as I am aware if your ps2 cant read discs then there is a problem with your laser and you will have to fit a new one Sorry Samuraicb
check out this link it might help http://www.cyber-mag.com/station/laserPS2.htm or if you have a v9 try this one http://www.cyber-mag.com/station/laserV9.htm