The timing on that second one is pretty nice 
Nice screenies!
My recommendation is to not reduce the size. If you want it smaller to upload or something, save that version under a slightly different name.
In fact, I prefer to always save the original intact, and always Save As.... with a slightly different name. That way you always have to original if you want to revert or mess up something.
As for the sharpening filters, watch using them too much. You'll notice the edges start to get funky on you. If you want to test them out, zoom in on an area with some lines in it and try different filters to see what they will do. And always modify on a copy.
Generally, though, I prefer to do minimal adjusting. maybe balance the colors a bit and trim the pic to display the focus better. But it's fun to go nuts with some filter work occasionally. 
My Deviant Art page link-link
CoH/V Fan Videos
Gaderath: Thanks muchly! It was all luck.
DarkEther: Yeah, I've noticed that with some that if I use sharpen, etc, then it makes it look better. But sometimes, it makes it look worse. Weird. Good idea with the cropping; I think I got the one in my sig fairly decently.
So I went on my first Praetorian mission the other day, and got these two shots of us putting the beating on Marauder. My video card is a little crappy, so I'm sorry that it's not the best.
When I have big screenshots like this, is it better to reduce the size a little, or play with sharpening filters? Sorry, I don't really have much knowledge by way of photomanip.
He hits!
We hit back!