Fellow Canadian here.
I second (third?) poring over the Canadian Couch Potato site. Also, Jack Bogle's book "The Boglehead's Guide to Investing".
I started out knowing Nothing about investing in late 2015, and over the past year have gotten comfortable opening a direct investing account at TD, and investing in mutual funds and ETFs. If you're worried about dumping all your money at one time, consider using dollar cost averaging (DCA) to put in a set sum each month over a longer period of time. Some people will argue that statistically you make more money dumping everything in at the same time, but given that your dad was burned in the past, that strategy may not work for you psychologically. DCA would help to get you over the psychological hump. You could also invest a smaller amount first to get your feet wet, and then, when you see how much money your money has made you, you'll be more comfortable putting in larger amounts. The point is to get started, no matter how small the amount, rather than to be paralyzed by fear.
For funds, each bank posts all their find information online. Do a search for the funds you're interested in, and look at the fund fact sheet, before you call the bank and schedule an appointment. My experience at TD was that the advisor works on commission and is likely to push the higher MER funds rather than the lower MER index funds.
Regarding the likelihood of a 7.5% return, there are some who say a 5% return is more likely in Canada in the next few years. Regardless of the actual number, it's most likely going to be more than the interest earned from parking the money in a Canadian savings account.