You should meet with a transfer counselor at your local community college. They will probably be willing to meet with you even if you aren’t yet a student. Also look on the bulletin board because UC counselors regularly visit CC campuses and perhaps you can meet with them.
One of the challenges you face is determining which of those classes are transferable but coming from a four year it’s likely that many of them if not all will be. You can find more on the UC website but generally transferable courses are going to be anything non-vocational or something like a PE class.
To improve your GPA you can repeat the courses and get a better grade assuming you got a D or an F in those classes. See http://admission.universityofcalifornia.edu/counselors/q-and-a/repeating/index.html. Of course an issue may be that your interests have changed and those classes are no longer relevant.
One long shot is to contact your previous school and ask if there is anyway to retroactively withdraw from the last semester or otherwise remove those grades from your record. Some schools offer academic renewal. Even if the chances are slim you’ll never know unless you ask. Read the recent threads in this forum and someone was successful in doing that.
Yours is not a simple case and you really would benefit by working with a counselor in person