There are software, some freebies on the net, that can encode 44.1khz PCM files onto a DVD. I use a software called MusicMagix I bought for about 1.5T at one of those Greenbelt software shops. You can even add picture files and navigation menu for each track or group them into albums that can be viewed on a TV. You input the CD tracks in WAV format. The software compiles these together with jpeg files you want into VOB files that any DVD player can read. The VOB files are played in LPCM stereo upsampled at 48khz.
In your case, since you're coming from mp3 files, you would need an audio editing software like NERO or Goldwave to convert each of these files into WAV. Come to think of it, the Magix software can also convert directly to VOB files from mp3, it will just take longer. There are freeware on the net that does this as well but with limited functionality. Check and download a free trial version of the Audio DVD Creator 1.75 here:
http://www.allformp3.com/audio-dvd-creator/(Not to be confused with sonic solutions' DVD Audio Creator LE which is a professional grade DVD-A authoring software costing $6,500 online)