-extensions:
. asx and asf are ms file formats for streaming video (more precisely, asx are textual files that permit to access asf files; asf files can be accessed on their own too)
. m2v is mpeg2 video (while mpg usually is mpeg 1 or 2, video or audio or both)
. vob is file format used in DVDs [some people rip the vobs from DVD to HDD in order to watch their film, HDDs being much more silent than some DVD players]
. ogm is ogg media; it's a file format than can be used for various content, just as avi.
I would not use bsplayer to play vobs (sometimes it works, sometimes not and your DVD player software should play vobs well enough)
otherwise it's up to you.
- subs synching
have a look at
fr0do's synching guide on doom9's site
BSPeter-addition: Another proggie to sync subtitles is SubSync.
I find it very easy and simple to use and it does its job perfectly.
You can find on http://users.pandora.be/vlad/subsync/index.htm