Hi Linda! Welcome to the forum!
I should recuse myself from answering since I'm a UCI grad, but honestly, if you get into UCLA, you oughta go there. UCI has improved itself greatly since I attended, but UCLA is still the number 2 school in the UC system, and holds more "clout". I wouldn't worry about this too much, though...if you decide to go to UCI, you'll still get a top-notch education.
As for majors, pharmacology at UCI is a graduate degree. I believe that it is a PhD program (maybe they let you "bail out" 2 years in with a non-terminal Masters...what we used to call a "consolation prize" for burned-out PhD grad students
). This shouldn't really be a consideration for you, unless you intend on doing your 4 years to earn a baccalaureate, and then commit yourself to another 4-5 years working on your dissertation for a PhD in pharmacology.
If you enjoy the sciences, by all means, major in the one that suits you. I like biology, especially microbiology. That's why I majored in Biological Sciences at UCI. You can still work on your prerequisites, and apply well before you earn your baccalaureate degree. As neonam said, there are many students who get into pharmacy school without a baccalaureate, so it wouldn't hurt any to try. If it doesn't work out, you can finish-off your baccalaureate and reapply.
Neonam also has a point about majoring in "non-traditional" areas, like humanities, literature, foreign language, philosophy, music, art, etc. Just as in med school applications, majoring in one of these non-science majors MAY help make you look more "well-rounded". You can still work on a non-science major and still complete your prereqs. I really don't know, personally, if this is a good route to take...I just remember hearing similar advice back in my premed days.
There are schools that take students out of high school. They typically have the students take 2 years of prepharmacy work at that school, and if they maintain a certain minimum GPA (usually 2.7) by the end of their 2nd preprofessional year, they are guaranteed a seat in the professional PharmD program. Most of these pharmacy schools are back east, Drake University in Iowa comes to mind.
When you have the time, please go to
http://www.aacp.org and go through the "For Students & Applicants" section for more information than I could possibly give you