Looks like you're exporting using the File > Export > Quicktime path. When you do that, AE (CS4, at least) shows a warning stating that this is not recommended. Now you see why this is not recommended
Use the Render Queue instead (Composition > Add to Render Queue). You can in fact just pick the pre-made templates for render items: the "DV NTSC" template for Render Settings, and the "Quicktime DV NTSC 48Khz" template for the Output Module.
You could be falling victim to some weird issues with Quicktime's DV CoDec when rendered from AE. Have you tried a more conventional Codec like Animation and let FCE handle the conversion? That aside, indeed using the RQ would be better than the legacy Export option...
I think the problem could be related to setting the (again, not recommended) Quicktime exporter to introduce interlacing, but of course AE isn't rendering fields. This probably leads to the file having half of the resolution.
Also, it looks like you're setup for a standard NTSC DV comp in AE, and your FC settings indicate anamorphic (16x9 aspect ratio).
Which one are you shooting for? Widescreen, or standard?
I'd render out of AE using the Animation codec and let FCP do the rendering. Use motion blur in AE, it's much nicer than FCP's, but let FCP add drop shadows or other screen effects. The anamorphic flag in FCP is going to cause issues no matter what you do. It may cause the Animation file to get squished on import to FCP or it may cause your render in FCP to be squashed. I try to always use letterboxing instead of anamorphic so all pixels from all collaborators' aspect ratios are solid and dependable. Most clients have no clue anyway as long as it's "widescreen."
maybe beteer is to choose tga sequence or png, which is good for text and is lighter than tga or tiff
bu do it in render queue.
make sure that all is set to full quality, and see if effects are applied