The Colombian arrived at the Santiago Bernabeu in the close-season - having helped his burgeoning reputation with a strong showing at the World Cup - for a fee worth close to €80 million.
James has since weighed in with 10 goals from 31 appearances in all competitions and praised Ronaldo for his assistance in easing the transition from Monaco to La Liga.
"His support has been fundamental," Rodriguez told Colombian station Caracol Radio.
"He's been a great help to me here and that's important. He's excellent, both on and off the pitch. A top guy, he's down to earth and his winning the Ballon d'Or was well deserved.
"I'm at the best team in the world and want to stay here for many years to come. I want to help the team to win titles.
"Of course I'd love to win [the Champions League] and I would love if it was this year, too."
James was also quizzed on whether he had won over coach Carlo Ancelotti following his big-money switch.
"He has a great way with the players and we're absolutely delighted with him," the former Porto man explained.
James' side will have to play without the 2014 Ballon d'Or winner after he was suspended for two matches following his sending off against Cordoba in Real's last league game.
