Avid DV Free, while discontinued, can be found as a legacy version on many different websites, and can be fully updated on avid's site, despite their discontinuing of the product. This is most certainly going to be your best bet, as it's the highest quality full fledged editing software that is frame accurate. Normally I'd just suggest windows movie maker, but it's such a hassle to make it do the most basic things correctly, and is NOT frame accurate, I'd much rather you went with an affective program than a program that looks simple, but ultimately doesn't work very well.
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