If no one spends bitcoins at all then the price of bitcoins will rise a lot .well thats not gonna happen near soon as people reply on bitcoins a lot for their daily uses and people who want to be rich a lot in the future wil not be using bitcoins.
I dont think soo that the price will rise up if no one spends bitcoin since there no activity on bitcoins ecosystem and also this thing would possible if the demand would arise and the supply would froze then thats the time that price will increase too.Bitcoin could possibly make us rich and it depend on how much we do have it.
I think if there is no turnaround in the market price of course bitcoin bitcoin will stop, unless the market more people are selling than the demand is there, of course the price will go down. but I think certainly there will always be people spending bitcoin
If the confirmation time is too long, people will not use it.