We hold the same faith now, if there was ever a time when we did not. We don't see any need to accept the other 4 councils, which mostly dealt with local matters. For example, why do we need to consider a council which we did not attend eccumenical, which ruled against the iconoclast heracy when we never had any problem with that heracy to be in need of a council to put it down? We have the same faith, so why do we need to worry about councils that happened a long time ago? No new aspects of the faith were understood for the first time there, the faith of the Church doesn't change. The 1st council was called when the emperor was upset about the fighting between the Orthodox and the Arians. So the matter was discussed, and the herecy was put down. We received the creed from that council, which is very beneficial, but the faith wasn't changed at that council, it was only defended. So why do we need to worry about councils that happened a long time ago in another part of the world over issues that never affected us?
Pope Shenouda offered to lift the anathamas between us, if the Greek Orthodox Patriarch would do the same. This would not achieve unity or Communion, but it would be an important first step in the right direction. Unfortunatly, the Greek Patriarch was forced to regretfully decline, as his people would have rebelled against him. They've been raised to consder us heterodox. The Church has been telling them for a long time that we are not Orthodox, and for them to turn around and say something different would cause chaos. When the anathamas were lifted between the Greeks and the Catholics, there was schism and thier primary monastary left Communion with their Patriarch (or something like that, I don't know the details). We and the EO are much closer than the Catholics, and yet for some reson there seems to be much more hate towards us. This is just a cultural thing, and not a matter of faith, but it is a main hurdle preventing us now.
There's a lot more openness and breaking away from old mindsets today, so maybe in a generation or two this hate that is separating us will have died away, and we'll finally be able to lift the anathamas.
One EO Church asked Pope Shenouda for full Communion between us, but Pope Shenouda had to decline, since that would only lead to more alienation between us and the Greek Church, which is in some sense in charg of the others (I'm not sure exactly how, but I know the Greek Patriarch is the first among equals somehow).
Currently, if an EO comes to communion at our Churches, and they are properly disposed, the priest will usually communicate them, with silent approval from the bishops. This is hypocrasy, there are anathamas between us, but there aren't many options until it becomes possible for the anathamas to be lifted. If one day the anathamas are lifted, it would make stuff like this more legitimate, and allow closer cooperation and less scandal, but there would still be some issues that could be a hinderance to full Communion.
For example, The Eastern Orthodox allow marriage to any Christian group, while the Oriental Orthodox only allow marriage within Orthodoxy. At present, if a Copt and a Greek wish to marry, there are provisions for this between the two Churches. But if a Copt wishes to marry a Protestant, they cannot go to a Greek Church to get this done. If we were to have full Commuion, they would be able to do this, and there would be nothing we could do about it. So until the rules about marriage can be agreed upon between the two Churches, full Communion would be difficult at best.
Right now the thing to work towards is putting an end to the unchristian hatred between us, improving relations, and hopefully eventually lifting the anathamas. The next step to take after that is something we don't need to worry about until we get there, there are enough worries for today.