i'm not sure for winxp, but check the "multimedia" or sound properties and look under filters/devices installed. see if your mp3 codec (Fraunhofer or Radium possible) is installed. i'm thinking if your program keeps crashing when u open a movie, means that the sound or video filters are 1 cause, not just BSplayer.
try this mp3 spund filter that i use, Odio Dekoda by Moonlight/Elecard:
http://www.moonlight.co.il/download/OdioDec.zip and see the forums at
http://www.elecard.com here. all the best in fixing it! =)