First off, I had to resort to copying the entire disk as an ISO file to the HDD. I just couldn't find a way to get decent quality rips of any animations (e.g. South Park). I spent the better part of two weeks and the last attempt was one where each disk took something like 2,5 hours to rip and it was still noticeably worse than the original.
Then I run into a second problem: some disks fail with dd ("input/output error") even though they work fine normally. I'd say something like 1 in 8 or 1 in 10. This was getting quite annoying, because re-reading didn't help. But now I think I found the solution. At least the last disk that failed was now read properly. And it only takes some 15-20 minutes per DVD so it's a quick process to transfer them to the HDD.
Swiss-army-knife wasn't very useful because it means you have to keep the projector on all the time. I want to use a command-line tool.
XBMC naming conventions have also caused some confusion, because the Wiki is somewhat, shall we say, sparse. Some stuff I have found out:
When a single file contains multiple episodes:
South_Park.S01-E01-02-03-04-05-06
When an entire disk contains bonus material:
Spaced.S00-E01-02-14
Check TheTVDB for episode numbers, and use 00 as season number.
When a movie is on several disks:
Pilvilinna_joka_romahti-cd1 and Pilvilinna_joka_romahti-cd2
Special characters (äåö) do not seem to work with XBMC name matching and in any case the English titles are shown even when the original title is in some other language so "Tyttö joka leikki tulella" wasn't being added to the library.
Remote works sporadically after the boot. Sometimes it works, sometimes not. LCD display doesn't work at all. And sometimes the HTPC device's output signal is identified incorrectly (don't know whether it's my A/V receiver or the projector) and it boots up in 720p @ 60Hz. Haven't figured out any other way to fix this than to reboot.
XBMC also crashes once in a while. Maybe it's the beta-quality video drivers, don't know.
On the plus side, once the files are correctly named XBMC reads the infor from TheTVDB and TheMovieDB correctly and they show up nicely in the Library. But we also have quite a few videos that aren't on those databases, so I guess the only way is to write descriptive nfo files for each of them.