Peninsula Visa will not be able to assist you in getting a Canada Electronic Travel Authorization (ETA) or Canada visa if you have a DUI.
If you have been convicted of driving while impaired by alcohol or drugs, you will probably be found criminally inadmissible to Canada. But as of March 1, 2012, you may be able to get a temporary resident permit for one visit .
You can read about obtaining a temporary resident permit with this conviction by Clicking Here
You will have to contact the Canada consulate / Canada immigration services directly for any questions and concerns about Canada visa requirements with DUI.