How to mount images without burning, PROPERLY?

Im an idiot, and also a rookie at mounting images to play games. Not much for playing the newest games on PC as i have an xbox360 for that. Rather, Id like to play some clic adventures like Monkey Island, Grim Fandago, Beyond G & E, Syberia 1& 2, Giants, Mafia, and some others. Mafia works fine, doesnt even need to be mounted. I DL'd alcohol 120% mounted Grim worked fine and had a bug where the screen went all screwy. Monkey Island mounted, worked fine but there's a bug.. it skips. Mounted Beyond good and evil.. screen goes black when start (could be resolution issue, will re-install and change) Syberia only comes in ISO.. DL'd poweriso and mounted the image, cant burn (no burner). Says insert cd even tho it comes with cd crack. Should i just go buy a dvd burner for $40 or is there a way to get these 2 run properly without? Am i on crack or are they all flawed and dont even work with cracks. If theres a trick to copying cd cracks etc. PLEASE HELP! Teach me your ways. message me.