Hi Lando,
As folks have said... it's not a simple decision to make and everyone is different... so you can't rely on our experiences to predict yours. It sounds like you have the liberty of time, so use it to find out as much as you can about the details of your condition and the options offered to you. And make sure you get a second, and I'd get a third, opinion before you proceed with any choice you make. In terms of ileo vs colostomy, the more bowel you have functioning the more normal your life will be... it's really that simple. You came from the factory with all that intestine for a reason. If we could function 100% normally with half of it... nature would have only given us half. That being said, underlying conditions tend to throw that oversimplification I just made right out the window. What I mean by that is for example... I'm short gutted with only 3 1/2 feet of small bowel. No terminal ileum, no colon. So I have a lot of output that's mostly liquid because all the bile my liver makes that's normally reabsorbed by my terminal ileum... isn't. So in my bag it goes. And without any colon the water isn't drawn from my stool to hydrate me. Sound pretty bad, but I wouldn't trade places with someone with a complete small bowel and most of their colon if they had any underlying disease. I'm completely healthy other than having a shitbag, but having Crohn's or Ulcerative Colitis still going on, even with a lot of intestine, would be a friggin' nightmare. So you can see how you need to weigh everything to determine what your true quality of life will be, and not just how much bowel you still have. Plus you're young, so you'll have the option of changing your mind and picking another path if the one you choose doesn't work out.
From the way you post your question I suggest you get more informed on exactly what your underlying condition is/was, and what each of the 3 options offered to you entails, and see if there are other options as well... that's where the 2nd and 3rd opinions come in. Don't rely on any doctor or surgical team, no matter where they're from, to dictate what path you take. You'll just regret it later. Do your homework and ask lots of questions. The right option for you will become very obvious the more you know about what your long term prognosis is and what's being proposed. And in the end you really do want to make the best informed decision possible... which only you can do. I know, it would be nice to just go to one doc and do what they suggest... but that, my friend, is a recipe for disaster. Because at 5:00pm they go home and forget all about you... while you're stuck living with their decision 24/7/365 for the rest of your life. And you have no idea what their true motivations are. You're luckier than most in that you've got time to figure it all out. Use it wisely and you'll be very glad you did!
;O)