If your Wii doesn't read games or crashes while you're playing, you probably need to replace your dvd drive laser. This repair is fairly complicated so consider using our Wii Repair Service if you're not too confident in your DIY skills.
Disconnect the laser cable first. The connector has two little "ears" on the sides. Pull those ears back at the same time to release the cable and pull it out.
The spin motor cable connector works the same as the laser cable connector. Disconnect this cable as well
This is the cable for the small circuit board that detects when the disk is inserted into the drive. It is not locked into the connector and can be pulled right out.
The two screws that hold the logic board to the drive are circled in green. Remove them. Circled in red are three small hooks on the drive. To remove the logic board slide it down a little so it clears the hooks.
Move the logic board out of the way and remove the screw in the metal laser cover.
There are two clips on each side and two on the front that hold the metal cover in place. Use a flat head screwdriver to pry/bend them loose. The metal is soft and easy to bend back into shape for reassembly.
Two more on the other side.
Two on the front. Pry them loose with a small flathead screwdriver.
Remove the cover being careful not to damage the laser cable
The laser rides on a small metal rod. To remove this rod lift up the plastic bracket (outlined in red), grab the rod with needlenose pliers, and push it out (direction of the green arrow).
Now you can remove the laser.
Your new laser probably won't come with the white bracket you see in this picture. To reuse it just remove the screw circled in red and install the bracket on your new laser.
Your new laser will probably come with an anti-static solder point on the cable. It must be removed before you install the laser. Use a desoldering braid and a low heat soldering iron.
This is what a properly removed solder point should look like. If you hold the cable up to a light there should be a clear "path" where the solder dot used to be.