The problem you're describing is usually caused by:
1) Burning to poor quality media.
2) Burning too fast.
3) If freezing/skipping twards the end of the movie, you're possibly burning too close to the disk's outer edge.
4) There is a possible incompatibility issue between your DVD player and the media you're using/trying to play in it.
Try:
1) Try another brand of media, like sony DVD+Rs(look for made in japan on the packaging), Verbatim, TY's.
2) Try and burn at no greater than 1/2 the rated speed of the media, but 4x is always a safe speed to start at or slow down to.
3) Try having DVD Shrink create smaller file sizes of 4300MB (or nero's recode 2), run shrink and goto:edit-->preferences, in the preferences tab choose custom from the dropdown menu and enter a value of 4300.
4) Make sure the standalone player you're using is able to play the media you're putting in it, so read the manual for compatible formats. If the player is old, consider buying a new one (they're pretty cheap nowadays) that will play all known formats. The only othe option for older players is to booktype DVD+R media as DVD-ROMs since all player will play that format. This can only be done to DVD+R media and your drive must also suppot it. Here's some info on it;
The last thing I would advise you to do is to make sure your burner's firmware is upto date, you can use Nero or DVD Decrypter to check what version you currently have installed, and use decrypter to check for an update for you (in the tool menu I believe).
