Mom.
We hung out more when I was growing up, and when I was 15 my parents separated and I lived with my mom. In fact, excluding one year living in the dorms at college, I lived with her until I was 22 years old! We've always been able to chat about anything and everything. I talk to her about once a week, and she visits every couple of months.
My dad is a bit awkward and quiet... it's just his personality. When you add in the fact that I'm a bit awkward and quiet, too.. it's just hard for us to talk much. We e-mail about once a month, and he visits occasionally, and we'll hike or hunt or do other activities, and it's always fun... but I still feel closer to my mom.
If you add together my dad's awkwardness and his curiosity about how things work, and my mom's neuroticism and her love of humor/laughter, you get me.