Unless you're a professional and want to spend $200-$500 Pinnacle Studio should fit all your needs. My video technique using Studio has improved each year. For instance - this year I figured out how to do picture in picture with Studio 8 using a DVD menu trick. I also bought Video Explosion Deluxe (10 bucks after rebates) so I can make pan and zoom of stills - I just turn them into AVI's and bring them into Studio. Also - Hollywood FX is a must (the cheap $10 version) to get all the cool 3D transitions.
If you want to mess with Adobe Premier Pro or Vegas Video both of them have free trial versions. I have looked at both of them. I haven't spent too much time trying, but I can't even figure out how to get to the screen to edit the video in either of those trials.
In Vegas Video - do you just have to drag the whole video to the timeline and then edit out pieces and stick it on another timeline? In Studio each video will appear above the timeline and I can cut chunks out and place it on the timeline. Then I choose another video and do the same, etc... How the heck do you do that in Vegas Video - anyone??