This may sound silly, but I don't do anything besides cropping and maybe a screen layer before I add adjustment layers and textures.
But I always make sure that I have good quality caps, usually from http://tv.rawr-caps.net/

What I always do at the end to take care of blurriness and pixels:
merge everything and paste as a new layer (Ctrl+Shift+Alt+E). Then I sharpen this layer and lower the opacity until I like the result. If there are pixelated areas, I merge everything again and smooth out the pixels with a small soft round brush.

Sorry I couldn't be more specific, but I hope this helps at least a bit.