It's pretty basic. You can edit and add transitions and music, but not much else. It has no capability of layering so you can't overlay one visual file over another. I opted to go with Adobe Premiere Pro. It's not cheap, but I really enjoy working with it.
However, that being said, I hear a lot of people like Sony Vegas, so have you considered tuning up your computer and seeing if that won't solve your problem? Have you defragged recently? Updated your graphics drivers? A few small tweaks to your PC could fix the crashing issues.