Cabs? From Airport, yeah take the bus both reliable and cheaper. In the city? Never had an issue with safety - as unbelievable as that might sound - Montreal drivers/cabbies can keep up with NY'ers no issue, they just swear differently. Cabs tend to be smaller than in most cities. e.g. Jetta, even had a Corolla once. Subway (called Metro) is good for getting around too.
Bagel place? http://www.google.ca/search?hl=en&q=bagel+montreal&btnG=Google+Search&meta=cr%3DcountryCA
Best place is not that close, St Viateur (if not best, certainly most famous) http://www.stviateurbagel.com/index/page/contact/?/session/7d475059e69d758022edff8ee7cdbb4e, maybe 10$ by cab, 24 hr lineups. Closer? 10 -15 min walk to a small mall/complex, le Faubourg just west of Guy & St Catherine, bagel place in basement. http://www.lefaubourg.com/english_pages/eng_aboutlefuabourg.htm
Alternative? Your hotel is in the core, many office buildings, and there is a massive undergound complex of cafes, stores etc.....most cafes will also offer Montreal style bagels. Ask hotel staff, they will direct you.
Laps? Again you will get some discussion here, but look for details on Cleo's here on MERB. 5-7$ cab ride from your hotel. Is sort of like Sundowner, but sleazier and much cheaper 10$/per. Other locations downtown vary for 15$ for same dance as Cleo's to eye-candy/air dances @ Chez Paris
Casino? Sorry don't have a clue - don't gamble
Weather? Bring a warm jacket, your uncle's thermal underwear, and buy a toque...if you do not know what that is, you will soon find out LOL. Just got off phone with uncle in south Texas - tells me it is 94F there. Bastard! Should be nice and cool for you in Montreal. Good luck.
PM me if you want to know more
