Which files do I copy from the discs so that the

[adeyke]

It is, indeed, the MPQs. AFAIK, the installation of the expansion already copied all the MPQs from the classic CDs (that's why you only need the expansion CD in the drive). So, just copy the d2exp.mpq, d2xmusic.mpq, d2xtalk.mpq and/or d2xvideo.mpq from your expansion CD to your Diablo II directory and I think it'll load them from there instead. You have to decide if the extra hard drive space is worth the extra speed.