Okay, bear in mind that I know nothing about video software. After crashing the first time I tried it after downloading the trial, I was able to capture from my DV camcorder right away. Good.
But opening the program took forever, because it loaded all of my numerous audio plugins. Why did it do that? Does it need to do that? Can I stop it from doing that?
I'm sorry but you haven't given us even remotely enough information to be able to help you.
What operating system are you using? Which version of the program are you running?
If you're on Windows, have you manually gone to Windows Update and downloaded even the non-critical updates? Have you gone to Apple.com, per the program's requirements, and ensured you have the latest version of Quicktime.
How much free, freshly defragmented space is on your C drive? When was the last time you run basic maintenance on your machine?
The program, by the way, will take considerably longer to open the first couple of times as it installs the necessary components.