16:9 vs 4:3 rendering issues....

So.....
heres my delema....

I shot a wedding recently with two digital 8 camcorders in the 16:9 setting, which i personally like better,
and had a third mini dv camera which was shooting in 4:3 ( i didnt know i could set it to 16:9 until just now. to late)

so what i have is two video tracks in 16:9 and one in 4:3
and im trying to throw them all together.

of course one of my segments is set at NTSC 4:3 which is giving my 16:9 footage the orange render bar because it doesnt like the frame size.

and i have a second segment dedicated to my 16:9 footage which is livid about the 4:3 stuff...

ive already started editing all the footage together without rendering, just viewing in realtime, but of course my machine keeps crashing because it cant keep up with both formats in one viewer on top of each other (which i did so i could sync up the footage with one another)

so now i have a third of the way edited project, which i can not copy directly from one segment to another to edit smoothly without the orange bar of death (which takes centuries to render on my old titanium powerbook)

what would the experts do in this situation?

export the only 4:3 footage out to 16:9 re-import it, and splice accordingly?

or is there some easier and faster trick besides rendering (which with the orange bar, if i blade through any of that rendered out footage th ebar comes right back again)