50i = 50 interlaced fields per second, at two fields per frame = 25 frames per second, so the correct frame rate for 50i is 25 fps.
A two cent opinion: you did the correct thing by switching to Pro Res as your codec, as ProRes will survive color correction/effects/graphics a whole lot better than HDV, and leave the frame rate alone.
Your sequence is (based on the screen shot) interlaced. Note the Field Dominance is set to Upper(Odd). If it is Upper (Odd) or Lower (Even) than it is interlaced. If you had a progressive sequence, it would say "None". Field Dominance give the instruction for which of the two fields to play first when displaying the frame. Since there are no fields in a progressive frame, there is no Field Dominance.
As to deinterlacing and delivering a progressive copy for your submission, since they accept the interlaced, why not deliver what you shot?
Someone else may have a different opinion, but I would go with interlaced.
Message was edited by: Meg The Dog to fix typo
MTD is the voice of reason here.
If the projection equipment can do justice to interlaced, go for it. Each codec translation introduces artifacts. The closer you stay to the original format, the cleaner the final (well, after dealing with the pesky issue of 4:2:0 material - best to get it to 4;2:2 for Color grading/ composting which is what ProRes does for you)