Yeah, your computer should definitely be good enough. You might want to check your graphics card settings on the "Hardware" tab of the "Application Options" (under "Tools") making sure it's compatible and such.
If all else fails, you could try reinstalling, but I'm not sure what this entails as far as keeping your license. I've used Inventor for four years, and I've found it to be fairly reliable and crash-resistant in my experience. Hopefully someone else has more insight on problems like this
