Converting from 29.97 to 23.98 in Compressor 3.5.3

I have some video that I shot that is at 1280x720 and 29.97 fps. I want to bring it into Encore and make a blu-ray disc out of it, but Encore doesn't support 1280x720 at 29.97, so I'll need to convert the video to 23.98 fps.

I just want to make sure I'm doing everything right before I convert...

In Compressor, in the Encoder tab and then under the Video Format, I put the Frame Rate at 23.98.

Under the Frame Controls tab, I turn the Frame Controls "On" and then under Retiming Control, I have it set at either Better or Best. However, what I'm really wondering is what I do with the "Set Duration To" section. Should I leave it set at 100% of source, or should I select the bubble "So source frames play at 23.98 fps?"

Also, do I need to make any modifications to the audio when it encodes in regards to the Retiming Control?

Thank you!