not always... a player's lens may become picky over time (hence, the need to calibrate it after a while ... a "well-used" player will need calibration sooner than a "moderately used" one... but these days dvd players are so inexpensive, most service centers will encourage you to buy a new player rather than having your old unit serviced.)
or the media is fine but the player is not "compatible" with it (this is especially true if the player is somewhat old). kung sa totoong pressed dvd nga may player na incompatible ... sa dvd-r pa kaya.
normally kasi, DVD-ROMs make better readers than commercial dvd players. the only solution here is to try another media and see how that works with your dvd player.
another possible scenario is corrupt data. the writing might be fine, but the data itself is in a format that causes the dvd player to hang. verifying the disc only checks for "write errors" but not the data itself. if this is an avi file encoded in an MPEG4 format or perhaps a "re-encoded" dvd-video, this is an additional factor you might consider. (a good example are the OGG encoded avi files that causes some standalone divx players to "hang".)
that's why i encouraged you to actually "play" the portion in your PC's DVD-ROM, if the portion where it hangs plays in your PC... then the culprit is probably the standalone player itself.