(a) Ripping CD's is sometimes very slow. There was one CD with some minor scratches that ripped at 0.9X (!). It started off at 4-5x, and then slowed down at one point, and never recovered. This may be due to the Samsung Drive, but I doubt it (see the next issue).
If you have secure ripping enabled (which may be the default), the rip will be guaranteed to be pristine, but rip speeds may be very low (often below 1x if it is a scratched disc). Secure Ripping re-reads sectors that misread the first time and makes sure the ripped wavform matches the original source data 100%. Typical ripping applications do not do this. They just make a "best effort" to read the disc.
You can disable secure ripping in MC's options, if you'd like. However, this means you could get inaccurate rips (like you would in iTunes or Windows Media Player, for example).
(d) Certain video files will not play on my TV (Samsung PN59D7000FF) when using the TV's built-in DLNA client. I believe these are avi files, but am not sure. I will check tonight and update this post if this is not the case.
Does the file itself play in MC? There are a few older codec types that aren't working right in the current public build of MC. It has been fixed in the betas, but they haven't been pushed to public yet. I'd guess that'll happen sometime this week or next.
Assuming they do play locally correctly, try updating the firmware on your TV.
If it still doesn't work, and you have the latest firmware, then the JRiver folks might appreciate a sample file if you can post one. In theory, I think it should transcode those on the fly when you play to a DLNA zone, but I don't know the details as I've not used that capability extensively.
I can't really help you with the DVD playback and ripping questions, as I don't use the DVD functionality (if I ever get a movie on an actual disc, which is rare, I just rip it using DVDFab, and have not tried playing back or ripping DVDs through MC in a long, long, long time. Someone else will have to comment.
