MCXCall 1-800-345-7669 and have your PS2 handy. Tell them you are getting Disc Read Errors.....
This is the best solution to the Disc Error Problem. I did this in late January this year when I start having problems with all my PS2 games (old and new). Called Sony, they told me to mail it to them, week after that, I had my PS2 back working like a champ... They even clean all the dust... No charge, except for the shipping to send it out. Depressed and desperate, I FedEx'd with next day delivery to Bristol NC. ~ $25.... But it works for me.
The solution of opening the thing works but is a temporary solution for all I understand. Sending your PS2 to Sony is a permanent solution because they replace the faulty laser or laser arm.