Houllier watched from the stands on Saturday as Villa were held to a 1-1 draw with Bolton.
The Frenchman officially takes charge on Monday and Ireland is looking forward to working with the former Liverpool chief.
"I think the change is going to have to be gradual," he said.
"Managers at other clubs have come in and changed things too fast too soon and it hasn't worked.
"I know Houllier has got big plans, and all the players will have to get on board. Hopefully we can go far in the cups and have a nice finish in the league.
"I'm happy with the appointment and everyone is looking forward to the future.
"Hopefully he can get the best out of me. The fans still have more to see. I'm still getting to understand the players on the pitch."