The Scottish champions would have been the more aggrieved of the two teams that the game was called to a halt after heading into the interval ahead thanks to a Steven Davis goal.
But, with a must-win Champions League tie against Unirea Urziceni looming on Wednesday night, Smith was happy enough with what he saw against an impressive United side ahead of the trip to Romania.
He said: "They weren't easy circumstances and I felt Dundee United started the game really well.
"For the first 20 minutes or so they were really aggressive in getting the ball forward and playing the ball into the box and they were dangerous at set-plays.
"We had to work very hard to stop them in that period and once we got the goal I felt that towards the end of the half we came into the game a little bit and had a couple of opportunities ourselves."
The Rangers boss singled out Danny Wilson for praise, with the teenager again acquitting himself well after retaining his place in the team following the midweek Co-operative Insurance Cup win over Dundee.
"I was pleased in that early period of the game with the way he handled himself," said Smith.
"At 17, it's not easy to come in and play. He has handled himself well."
However - with Madjid Bougherra and Lee McCulloch both still struggling with injuries - he was tight-lipped on whether he thinks Wilson is ready to be pitched into a massive Champions League game.
"I don't know," he said. " We will see once we get nearer to Wednesday night."
Despite being denied the opportunity to edge closer to Celtic at the summit of the SPL, Smith backed the referee's decision to both allow the game to go ahead in the first place and to abandon it when he did - views which were echoed by United boss Craig Levein.
He said: "At the start of the game there was no water on the pitch and you could see for the first half-hour that the ball ran across the top of the surface quite well, quite slickly actually.
"But in the last 15 minutes of the first half you saw people sliding on the pitch and into advertising hoardings so the referee has made the right decision and I don't think anyone would argue with that."
Unirea Urziceni Evens, Draw 9/4, Rangers 3/1