I've found parties pretty fun when I've had them. If you want a more relaxed party you can uncheck the goaled event checkbox. I don't stress much and let the quests wander, they usually go to dancing though! So plan carefully where you place your stereo. I was also going to suggest the create a group (not club) option to control the guests if you want them in a certain place, but it's been mentioned already by @mightysprite . I always lock my computer either for parents only or household only. I don't think guests should be taking showers, that doesn't sound normal.