They're going to have to give you a bit more info. MPEG2 can be Elementary stream with separate AC3 audio for DVDs, Program Stream, Transport Stream. This is HD so DVD doesn't fit this equation. If you need to encode for Blu-ray there is no preset for that in Compressor (there is for the defunct HD-DVD).
Basically your going to have to set Compressor to encode to Blu-ray and create an MPEG-2 Program Stream.
Here's one tutorial from Ken Stone's site
http://www.kenstone.net/fcp_homepage/blu-ray_fcp_fields.html
Here's another from Adobe
http://blogs.adobe.com/davtechtable/2008/04/apples_compressor_encore_blura....
If they want a more efficient file size you could use Matrox CompressHD which does H.264 Blu-ray encoding, has presets, works inside of Compressor.
You really need to talk to them about what they need since HD for Blu-ray isn't quite the same as SD for DVD.
