Several things.
Many editing apps, inc MM only show low resolution previews.
Video is interlaced to be shown on tv's so never looks quite as good on a
pc monitor.
You captured as a lower resolution format, like wmv, instead of dv-avi.
If these are stills it may be the apsect ration size needs changing, use a
4.3 size, like 640x480.
If they are stills, use a stills slkide show editor like photostory free
from MS for best results, rather than a movie editor like MM.
