interlace / field dominance question...

I have noticed an issue with the video I am exporting - with the movement of the presenters hands - lines appear...

I had been selecting 'de-interlace source video' which I thought gets rid of this but it doesnt seem to make much difference.

I then did some searching and found that I can alter the field dominance. It was set to 'lower' in the sequence settings and I found that setting to 'None' gets rid of the horizontal lines...

However...I have a short intro graphic I created in Motion at the start of the video - and I have noticed that when I set field dominance to 'none' this intro looses all its sharpness and looks a little rough round the edges of the writing...

Is there a solution so I can have the best of both worlds? FYI these video clips will only be viewed on computer screens...

Thanks in advance