It doesnt register that there is a disk in the console

This happens to me , Some games don't work on Some PS2 consoles for Example my friends Theme park world only works on a Slim PS2 and not a Proper Fat one , Wat type of PS2 do u have? and wat game r u trying to play?

no... theres definately a bad connection jiggle the yellow wire.. if that doesnt work try a different set of A/V jacks, if that doesnt work, try a different game

If its standing up like in the picture just put it on its side and if that doesnt work for you just look in where it reads the disks and look for something wrong then search the problem or just tell me and ill do it for u.

Alot of ps3are not capable of playing ps1 or 2 games.

Yes I see your problem!
1)Did You Drop the ps2 at all?
2)Maybe Your using the wrong disk...(like old ps1 or copied ps2 games)
3)Maybe it just stopped working...if You got it recently go get it exchanged or fixed(check the warranty)...
4)if it doesnt turn on then its most likely broken or messed up...
5)if the game doesnt work it may be scratched or need to be cleaned
6)clean the ps2!get a computer/game console sprayer...
7)they also have cd cleaning devices that get rid of the scratches (not too big or long though)

it could be that the format of ur disk doesnt match with the ps2

this has happened to me before and this was due to a disk format malfunction, you will need to take it back and get another one.

It needs a new laser installed.

Do you see the startup logos when you turn it on?

Try Cleaning Your Laser