Th easiest way would probably be to copy and paste everything into a 4x3 SD timeline with the proper framerate. If the video looks squeezed or distorted in any way you might need to delete the distort attribute for all clips. Then just export as QT Movie at current settings and use that file or bring it into Compressor to create a Web video if that's what you need.
David Roth Weiss
David Weiss Productions, Inc.
POST-PRODUCTION WITHOUT THE USUAL INSANITY ™
A forum host of Creative COW's Apple Final Cut Pro, Business & Marketing, Indie Film & Documentary, and Film History & Appreciations forums.