The Greece international, a huge favourite with the Parkhead fans, fired the Hoops in front on five minutes and a fine strike from Tony Stokes completed the scoring 19 minutes later.
Samaras' deal is up at the end of the season and Lennon fears his talismanic striker is heading for the exit door after six-and-a-half years with the club.
Speaking to Sky Sports News he said: "It's still open to debate at the minute. There is no forward movement on whether he stays or goes.
"From my point of view I would like to keep him as he brings something different to the team, but Sami will have his own perspective on that.
"There may be a bit of movement yet but at the moment it looks like he won't be here next season, but while he is I think he owes it to the supporters to show he is still a quality player.
"I know him better than anyone and knew I would get a big performance out of him... as I did with Beram Kayal, so I am very pleased with their contributions today."
On the game itself, Lennon said: "I thought from start to finish today we were brilliant.
"There has been a lot of nice things said about Dundee United and Aberdeen recently but what gets overlooked at times is just how good we are.
"We want to put a marker down for the rest of the season and I thought we were absolutely fantastic and should certainly have won the game by more than two today.
"This is a good ground to come and play against a good team and it's always a great atmosphere and we wanted to do the fixture justice. I thought at times some of our football was sublime.
"Kris Commons was the pick of the players. It's difficult to single out anyone but he was magnificent and Anthony Stokes carried on the great form he has been in recently.
"As for the two lads coming in - Samaras and Kayal - they too had great games. I know what they can do and they showed that today and we looked a very good team today."
Dundee United boss Jackie McNamara agreed with his former team-mate's summation of the game and will be looking for a better display against Rangers in next week's Scottish Cup semi-final at Ibrox.
"It is imperative for us that we start the game well and don't give up any silly goals from set-pieces because Rangers will hurt you, especially with set-pieces," he said.
"I have belief in the players. We are a young side but we will go there and do
our best, and if we play as we know we can cause them problems.
"If we play like we did today in the first half, we will give ourselves problems rather than them causing us problems, so we have to start the game well."
Watch Dundee United take on Rangers in the Scottish Cup semi-final next Saturday live on Sky Sports 2 from 12.30pm