Broken system


Hi i bought my mac mini 4 months ago and have been very statisfied but recently things has goten very anoying,for some reason i cant use os9 applications anymore i had this working fine a few months ago,and now X11 dosent work either,i have tried to install X11 and os9 many times but none of them work anymore,also i downloaded a demo of potoshop wich hangs so i am soon takeing the decision to re-install tiger,but i dont know if i'life 05 comes with it on the dvd's,garage band was the whole reason i bough my mac in the first place,so i am wondering is there a way to fix my problems or should i reinstall,and one more thing is there a uninstall manger like in windows in osx? i mean everytime i wanted to uninstall something i have just droped it in the trashbin as i havent found anyother way to uninstall applications even if it had a installer:|