"Infose, financially how much damage will the ECB and EU nations...

"Infose, financially how much damage will the ECB and EU nations have if Greece defaults and the total debt is wiped out?"

The damage will be direct and indirect. In the case of Portugal the dirct damage would be around 4 or 5 billion but th potential for indirect damage can be substantial. As you know Portugal is considered to the second most weak link and if Greek defaults then investors may start deserting that country pushing their interest rates up. However, it is expected that the ECB will step in buying the Portuguese bonds.