OK. First of all, put any disc in and turn on the PS2. Push the spot shown here down with something about the size of the TV end of the AV cable.
http://i142.photobucket.com/albums/r96/Daiv_The_Goriya/Pushdown.jpg
Watch what it does. Does it stop spinning? If so, see this pic
http://i142.photobucket.com/albums/r96/Daiv_The_Goriya/PS2problem.jpg
- This keeps the disc from spinning when the cover is open.
- push this down while following the instructions from the first pic. Does the disc work?
- There's usually a small object that pushes #2 down. Chances are it broke off.
http://i142.photobucket.com/albums/r96/Daiv_The_Goriya/Missingpiece.jpg
This piece here is what broke off on my PS2 as seen in the previous image. If you can find some way to glue it back on, you should be back in business.