To make thing easy, pre-1967 war borders. 

Fifty years of settlement and martial law has lead to quite a lot of dysfunction in the occupied territories, both from occupied and occupier. 

Its time for the Israelis to remove their settlers and army from the West Bank and go back to Israel. The territories are not part of the state of Israel's legal boundaries, and de facto is not a good precedent for Israel to be setting for itself (i.e. it can then go both ways).