Personally, I use a program called Reaper
. I like it because it's fast, rock stable, immensely powerful, highly customizable, and cheap. Easy to use? Well, I don't think it would take top honors there, but if you take some time to configure it and read the manual it's as good -- and in some ways even better -- than just about anything out there.
That being said, never stop experimenting with new programs. Of all the tracks I've made, some of my best were with a homebrew music app for my psp called Rhythm. Even with it's massive limitations -- 16 note polyphony anyone? -- it's proved useful and creatively inspiring to me. When your creative vision is not clear, absolute power and endless options can be your worst enemies. The decision on whether to set those limits yourself, or use tools that set them for you is one everyone has to make; both approaches can lead to great work.