Solution: installed 2nd hard drive, 250G, loaded Vegas only on 2nd drive, and keep all related medio and 2nd drive. Had to resize all stills, most around 655x480 which is limiting. Have about 300 stills, audio tracks, text, menus in all. runtime about 38 min and no hangs. Program loads with project in about 20 seconds.
Hope render and burn in DVD Archictect goes smooth. Thanks for all your input.