How do I fix broken PS2s (disk reading error?)?

I have two broken.



One says there is no disk when there is one. It is a slimline.



The other plays some games but is slower on others (slow to load, music skips, disk makes lots of noise and pauses - games workin eyegame, medal of honor, games NOT working sims2, Urbz)

It is an original chunky ps2.



Is it something I can fix them my self, can you tell me how or is there a site with instructions and pictures?How do I fix broken PS2s (disk reading error?)?
Try cleaning the lens with a rubbing alcohol and a cotton bud. If this won't help - the laser must be replaced.How do I fix broken PS2s (disk reading error?)?
Well, the Fat PS2s have had some Laser problems especially with a gear under it pushing something up and scratching the laser and the disks. That happened with ours and it got so bad that 1.) it ruined one my my favorite games and 2.) i could not play it at all because it started to skip on stuff. For ex., i was playing Resident Evil, and i got half way through and the game paused and i could not do anything, it then did that with all fo the others. For the Slimline, i have NO clue... Sorry... :(How do I fix broken PS2s (disk reading error?)?
get a new one. cheaper than repair costs, you can get refurbished ones for less than a hundred bucks.
I REALY DONT KNOW