The Ottawa river is a lot more forgiving than Lake Ontario. Don't worry about the rapids, just turn left when you leave the NSC channel and you won't be anywhere near that danger. I've sailed on the Ottawa (out of BYC) for about a half century, it is extremely rare for anyone to go down the rapids. There was one a couple years ago but that was a pontoon boat and they had no clue the rapids were even there, just drove right down, so you are already way ahead of them.
Let me know if you have any questions about local knowledge. I've hit most of the reefs myself
I've never launched at NSC so I can't help much but I do know people that sail out of there that may be able to help. I've never rigged a Hunter 260 but feel free to contact me (PM for contact info) and maybe we can meet up to get your started. I've rigged and sailed more boats than I can count.
I really (really, really, really) recommend you contact Advantage boating and sign up for the basic cruising course. Ask about having them train you on your own boat; it will be way more help than you can possibly imagine. If Ron or Doris answer the phone, tell them D'Arcy sent you. I'm not affiliated with Advantage in any way, I've just sailed with (and raced against) them for many years.
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