You can make money with Flash games, most people use advertising code on the intro of the game, some generate money regardless to whether the player clicks on it or not
a game I did in 2007 has been played more than 250.000 times, IF (bursts into tears!) it had this code even at googles rate of .03p a click it I'd be laughing to the bank.
Getting a flash game noticed takes no effort at all, you post it on a gamers site ie Gamershood and before the days out it'll be on most Bloggers sites by the end of the day
Downside, you need a server with lots ior unlimited bandwidth, or you need to get someone like Newsground to host it, a 5 meg game, once popular can gobble up 1.5gb in a days .
If you look around right now there's on avarage of 10 escape the room games released every week, regardless to whether they are good or bad they end up global and make money
You would need to invest in Flash, TBH Flash 8 is all you'd need and there loads of tutorials,
this oneis considered the holy grail for tile based Flash