Can vegas 7 or 8 do live shooting & capturing into laptop?
 

For shooting static shots such as a conference or stage play, I wish to use a laptop to direct record. Is vegas able to do it?

Yeah, Vegas can do that. It works pretty much the same as any other NLE. Plug in the camera through firewire and you should get a "live feed." Just hit capture and you're ready to go.

Don't forget to turn off "device control" in the capture preferences, or vegas won't like your camera much when it's in camera mode.