Pinnacle Studio 14 HD
Have you tried Pinnacle Studio 14 HD ?
Adobe stuff is a power hog and its UI menu's are overwhelming sometimes.
iMovie confused me as well with its UI and how it forced you to do certain things that didn't make sense.
After getting frustrated like you with other types of software, Pinnacle Studio turned out to be the best option. Earlier versions crashed quite a bit but the latest edition seems stable.