Do you own the Platinum edition, or the plain Movie Studio Edition? Make sure you run the latest version of Platinum for the HD2000. If that still crashes, upload on a server somewhere 3 seconds of a 60p file out of this camera so I can try it here.
BTW, it's not a big surprise that Vegas crashes with these files. Any file format that uses Quicktime to decode on Vegas is very crash prone. This is why I use Cineform NeoSCENE to transcode my Canon 5D MarkII's h.264 format to lossless AVI.
I own the platinum edition 9.0b. I tried the Cineform Neo scene only to find it wouldn't allow me keep my native 60fps; it converted to 30fps. I thought it was a quality program, but frustrating to lose the 60fps. I'm not sure where I can upload some video for you to test. Thank you for your reply!