> Is it possible that HTTrack downloads only graphics of a 
> certain size?> For example fullsizebanner with 468x60 pixles.

No -- but you can filter based on the FILE sizes.

-*.gif*[<10]

Will break all gif downloads for files smaller than 10KB

-*.jpg*[<10>200]

Will break all jpg downloads for files smaller than 10KB or 
greater than 200KB