i was planning to go Canada sometime ago for only fun. however my attorney recommended not going. Basically he said if you went to stamp visa( change from h-1b status to h-1b visa), then go. otherwise, stay. I also realized lots of those people are not immig. officer and they don't have all the correct knowledge. However they don't want to risk to change a goverenment agency particulary after 911. I feel very sorry for you. you might consider to contact the customer service and see if you can get refund.
I know you can go Canada and back in 30 days with no problem. HOwever if your dad is B-2 visa, he can not except he has mulit-entry visa.