The majority of BDs released today have either a Dolby or DTS lossless track. However, many older BDs have PCM tracks and a fair amount have lossy Dolby or DTS soundtracks.
You shouldn't be able to tell any difference between PCM and the other lossless tracks. You may or may not be able to tell the difference between the lossless tracks and the lossy tracks.
It's worth pointing out that Blu-ray can use a much higher bitrate for their lossy tracks, so they usually sound better than DVD (and may sound as good as lossless tracks; this is a controversial topic). It's also worth pointing out that many BDs do not default to the lossless tracks, so you might want to swap between the various tracks and see what's available (or go to the audio setup menu).
You shouldn't be able to tell any difference between PCM and the other lossless tracks. You may or may not be able to tell the difference between the lossless tracks and the lossy tracks.
It's worth pointing out that Blu-ray can use a much higher bitrate for their lossy tracks, so they usually sound better than DVD (and may sound as good as lossless tracks; this is a controversial topic). It's also worth pointing out that many BDs do not default to the lossless tracks, so you might want to swap between the various tracks and see what's available (or go to the audio setup menu).