O'Neill said: "I wouldn't want to be saying how confident we are (of keeping Barry). It's a different era we live in. We will see. All I know is he has never expressed one iota of unhappiness in my time at Villa Park. He might not have stayed that long had he been really unhappy before. We're going to be sitting down very shortly and discussing Gareth's future. We won't let this lie.
"I'm going to see the chairman in the next couple of days with a bit of luck and the two of us together might be able to persuade him to stay. I say persuade him - but he still has two years left on his contract."
O'Neill added: "Gareth is a demi-god at Villa Park. He has that reputation and he's playing for England and he hasn't had to move to another club to do that.
"He has been particularly brilliant for us. We want to improve the team and our best chance of doing that is to keep our best players and adding some quality."
Barry admitted he had been affected by all the speculation over his future but was back to his best in the 2-2 draw at West Ham which secured an Intertoto Cup spot.
O'Neill said: "Gareth might have been affected by the speculation last week but I thought he was back to his best yesterday against West Ham. He did splendidly for us. You wouldn't have thought he had anything else other than a win on his mind."
Villa have already rejected one £10million bid from Liverpool for Barry and there has been a war of words between O'Neill and Rafael Benitez over the possible deal.