Not dumb questions.
ProRes is a proprietary codec that is licensed by Apple. You will not find the option to export to ProRes in any Open Source application that is distributed freely. Awhile back, somebody came up with a prores workalike hack... not sure what the status is of that these days... better to use genuine Apple since you have it anyway. For that matter, it is better to encode to H.264 in Quicktime than use the freeware apps as well. Apple pays the license for you and you have the genuine article available.
I find the UI for VLC to be confusing and mostly annoying. It is definitely not a native Mac App. Leaving those two options at 0 is "code" for "use the original format". The Maximum bitrate for DVD was around 8000kbps (8MB/s) but
the average was around 5MB/s. If it's an American DVD, then the frame size is most likely 720x480... It's original codec is MPEG2 and no matter what you do, it's going to be converted to ... something else. If you use a bitrate of anything other than 0, then use 8000-10000kbps. More than that is basically useless. For the framerate, if you don't know, don't change it. If it's 29.97, go ahead an change it to 30. NTSC was just a counting game - skip a frame *number* every so often except at 10 min intervals...
ProRes, at least, will *not* degrade your original in any way. If the footage is interlaced, keep that when you convert - remove it *IN* FCPX, not in any of the converters you use. If you're lucky, the original will be in "progressive" format (not interlaced.) After you move it into FCPX and there is interlacing, MPEG2 interlacing was Lower First (Field Dominance Override — set in the Settings Inspector) — do not "lie" to FCPX, it will screw it up. You can check the Deinterlace option if you like, but I don't think it makes too much difference — try both ways and see what looks better.