What is the ruling on arranging Quran CDs alongside CDs containing sins, or pictures of naked women, or pictures of games that violate Islam on the same device? And is playing something forbidden on a device that contains the Quran considered a mockery?

You must dispose of CDs containing unlawful material. If it is possible to reuse them for recording the Quran and Islamic rulings, that is good. Otherwise, it is obligatory to destroy them. Merely placing these CDs with others that contain the Quran is not an act of mockery or disbelief. Similarly, playing unlawful material on a device that contains the Quran is not disbelief, but it is prohibited.