MythTV has its weaknesses (mostly UI related), but I'm not sure what you mean by this:
Does it record to two files if the shows overlap (due to begin/end padding)? Or does it still decide the two shows conflict, and records only one, or records both but only one partial?
The answer: it depends. MythTV will do the following: if possible, it will record each show in its entirety, with the padding requested by the user (this is configurable on a global and per-recording level). Say you have show A and show B, where show A ends at the same time that show B begins: MythTV it will do its best to preserve both shows, but it's limited by how many tuners you have. With two tuners of equal priority, MythTV will record show A on tuner 1 (including any pre/post padding) and show B on tuner 2 (also including any pre/post padding).
If you only have one tuner, then MythTV obviously can't do that (indeed, no DVR really could). What happens in this case is that MythTV "throws away" the padding in its calculations; so it records show A (but no post-padding) and immediately switches to show B (with no pre-padding). In an ideal world with good schedule data from the TV stations, that would be good enough, but shows often run over/under (which is why you have the "padding" option), so in this case you might lose a few seconds of each show (assuming A runs long and B starts early). MythTV figures that the padding is "nice to have" but, if it can't guarantee that padding, it also figures you'd rather have the show as scheduled than no show at all.
By the way, if you dig deep, most of these things can be modified. MythTV's defaults in this case do what I believe most people would want to do, but they can be extensively modified to taste.
Does mythweb has a record button on the shedule overview? or do I still need to go to the show page, change the state to record, save, and then go back to the shedule?
I don't think it has this as of .22 - it would be handy.
Does it play DVDs out of the box?
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This is distribution specific, and it's not a MythTV problem. In the United States it's illegal to play DVDs in Linux without paying for a decoder license. Many distributions give you easy ways to bypass this restriction at your own peril, and in gentoo with the appropriate use flags everything does indeed work "out of the box."
Does it allow me find© the recorded files to another machine so I can watch them on the road? (searching trough the hashed filenames is no fun)
Mythweb allows direct download of files.
Basicly, MythTV is great for a power user, but is really sucks for the basic user.
I do agree with that sentiment. It does/can do most of what you desire, but it's not obvious due to a murky UI and rather cumbersome setup process. If you aren't interested in tinkering, it's a poor choice.