I've been a tech for three years, and I start my first RN job (ICU, panic!) next week. I can tell you from personal experience (I've worked LTC and orthopedics in those three years, so geriatric is a huge part of it) that you get used to poop. When I went into healthcare, I started as a tech to make sure I could handle it. The thought of cleaning up poop and wiping someone else's bottom grossed me out, but I said "I can do this" and I did. While I certainly didn't enjoy it, after a few months, it just became part of the job and no longer bothered me. However, if poop is a make-or-break for you, how about you look into something like postpartum? Your mothers will, for the most part, be up and taking care of their own bodily functions, if you catch my drift, and though you'll have to assess that area, you probably won't have to wipe as many butts, as you put it
. You may have to wipe some tiny butts, but they are so much cuter when they're only a day old.
As far as the death and dying goes, that is a part of life, and you'll have a hard time getting away from it. There will be areas where you will see less of it, or see it very rarely, or may have to deal with families less when it happens, but I can't think of any areas that are death-proof, so to speak.
So that's my advice: go somewhere like pediatrics or postpartum. There's no shame in admitting an area isn't for you. I started out in nursing school thinking I would go pediatrics, and came out of it going "omg, I will NEVER go pediatrics." But that's the wonderful thing about nursing: there are so many different areas that you can go. Look into a transfer, and don't let wiping butts discourage you! Best of luck!