Hand 1 is a preflop push-fold spot, and we just use software to get the answer for these simple situations. Because you are so short and already in the money, we can basically just calculate the NASH equilibrium in chip EV mode, which a lot of free software can do. ICMizer can also do it, and the answer is SB jamming 71% of hands and BB calling 75% of hands. So basically both players are supposed to get it in with anything but junk, and JTo is a solid call. If for some reason you think, he is not jamming as wide, as he is supposed to, you can tighten up a little bit but JTo will still be a call.
In hand 2 presumably you were facing a minraise or something along those lines, and someone had already called. I would certainly not call and try to setmine out of position with such a short stack. But jamming could be a reasonable option, if you think, the field caller will usually go away, because then there is a decent amount of dead money in the pot. Personally I probably just fold though, because I will rather find a spot, where I can open jam with fold equity.