It has been said that one needs to talk with one's enemies. Talking does not mean surrender or giving in to their demands. All things being equal I agree with that concept. But unfortunately things are not always equal. In the case of Hamas, we (and by we I mean my country America and its best Middle East ally Israel) should not at the present time talk to them. The reason is not just that they are our enemy. Not only do they not even acknowledge Israel's right to exist, are openly pledged to its destruction, and continue to attack Israel by shooting rockets over the border from Gaza, but they are at odds with Mahmoud Abbas and Fatah. Fatah is not exactly our best friend, but they under Abbas are at least willing to talk about peace. The problems are in the details and in the question of whether Mr. Abbas has the ability to enforce peace on his side. There was a real chance of peace just before the intifada, because the people on both sides were developing a sense of trust, but Yasser Arafat blew it all away with his intifada. Renewing that lost trust will not be easy but must eventually happen.
The reality is that now there are 2 Palestines, one on the West Bank under Fatah and the other in Gaza under Hamas. If everyone including Fatah could accept this reality and Abbas were no longer responsible for Gaza, then it would be easier for Israel and the West Bank to make the compromises necessary for peace. Gaza would remain the enemy, but perhaps if the Gazans see the fruits of peace that the West Bankers reap, they might realize what losers they have chosen in Hamas and get rid of them.