KOTOR was actually the game that got me into RPG's in the first place so it allways has a special place in my heart, however the bugs you encountered are most likely due to your over powerfull hardware for the game, there are some things you could try like getting an optimizer, running in WINXP compatibility mode and check www.kotorfiles.com for some fixes,
Mass Effect is atm my favorute game series, its the star wars of modern games and what really draws me to it, is its story,characters and how cinematic it feels, when it comes to actual RPG gameplay its pretty poor in that regard compared to other Bioware titles
Dragon Age would be my recommendation if you cant find solution to your KOTOR problem, Its your typical "old school wrpg" turned into a modern game, it has very long lenght, lots of stuff to do, interesting characters, the world you live in looks and feels great, its not perfect world of sunshine & rainbow: violence is everywhere, there are poor people who live in the slums, political backstabbing and the title RPG fits in every sense of the word for the game, you have alot of character customization, playing with numbers and interesting gameplay, story is okay but like most of the WRPG games its not the ending that makes it great, its the journey,
some people praise old games like Baldurs Gate,Icewind dail, Fallout 1,2 but lets be honest, those type of games arent made anymore, they arent beginner friendly and the outdated graphics and walls of text only burn your eyes out of their eyesockets