You can do it that way if you like but I have a better solution for you.
It's always better to capture and edit at your original resolution i.e. 720x480 (or whatever

) and only whenyou have done all your editing and you do your final export as a movie do you reduce the size. At export time there's plenty of options to change size.
If you do this then if it is a masterpiece you have a full sized original and can re-export it at full resolution for any purpose you like rather than be stuck with a tiny version only good for dial-up connectes, say.
For example, I always shoopt and edit in high def. Only at export do I shrink it down to standard def for DVD production. Later, when I get a Blu-ray burner (or whatever) all I need to do is re-open the project and just export it with different settings and not have to do everything again.
See where I'm going?