Thanks everyone who took the time to reply to my question. The idear of the subject message was to get more replys which it did as I love using Vegas to edit. Reduce interlace flicker fixed near all of the problem but a few fast moving shots (which I have now replaced) I may be tempted to go for one of the systems suggested by Art
( you could just buy a mac, final cut pro, or avid excess, and not only will it do pip for you all by itself perfectly but it will make your coffee and fluff your pillow at bedtime!)
Thomas