Unable to load games

I have a very similar problem that my wii console gives me black screen with disk read error every time I inserted a new disc that worked previously. The way I worked around this problem is by
1. ejecting the disc
2. powering off(hold the power button for about 10 seconds)
3. unplugging the power cord
4. waiting one minute or so
5. plugging in again and re-inserting disc
This worked every time when I switched disc.

Please don't suggest "putting the disk in the other way around". Duh. This seems to be a real problem, could it be a scratched/dirty/damaged CD ? or faulty reader ?

put disk other way and it WORKS????????/