The details of DTS 96/24 are on the DTS website but in general terms it allows 96Khz/24 bit sound on 5 rather than 2 channels. In theory, very good news; in practice there are probably more hens teeth lying around than DVD's with a DTS 96/24 option on them. Try a search on this forum and the DTS site for listings.
To benefit from this format, the receiver or processor needs to have suitable software to decode it. As most new receivers etc will have this capability, you will get it anyway if you buy a new one. I certainly wouldn't update my current receiver just to get it.
three discs available at present, one sounds very obscure the other two i have and have tried in 96/24
didn't compare with non 96/24 receiver as still wouldn't be a fair comparison
but they sound amazing
(Queen greatest hits1 and 2) (Region 1 I think)