The 6600GT would be more like it, but even that would be more powerful than you would need for video editing, yet, its a rather cheap card in todays terms, and if you decided to play gaems, would keep you going a while.
"Geforce 6800GT 256MB GDDR3 PCI Express x16 Video Card - Retail"
would be overkill, as you definietly would not need a card that powerful for editing, trust me. You wouldn't even need as good a card as that if you were 3D modelling, etc.
As for the Raptor, yeah, it was good to drop one as they are too expensive really at the moment, and upping the amount instead
The RAM also was a good part ot upgrade as this is what affects video editing the most.
SPEAKERS AND SOUND?:
As for this:
"Logitech X-530 70 Watts 5.1 Speaker - Retail"
If you watch movies, etc, it'll be a great choice, and also if you decide to mix 5.1 surround sound into your editing, plus they are really powerful too.
If you wouldn't watch movies though, and wouldn't want to mix in 5.1 and only stereo, these are a slight overkill. Great for music too though of course.
As I'd call it though, you are more than likely to want a better sound card than the one thats built into the motherboard. Why you may ask? Well, it runs off your system slowing down performance, and doesn't allow as much features as a dedictated sound card would.
So if you don't want surround, you could drop the 5.1 to possibly a 2.1 (The same make and set), and get a dedicated PCI sound card instead to save money. This would be alot better trust me than sticking with onboard sound, and the quality will be immencely better too.
You could always stick with the 5.1 though and get a better sound card.
The Sound Blaster Audigy 2 (Or one of the newest ones, though even an older Audigy would be fine, as they just seem to increase the speaker values) sound card wouldn't go amiss, as this supports alot of features built for editing/sound mixing which might be useful for editing video.
Plus, if you get a Digital Version of it, it'll come with a front panel for adding sound devices easier, etc.
Or this if you aren't bothered with some of the features, but still will give you immencely better sound over onboard:
I hope this helps