The main difference between using the likes of Pictures to Exe (PTE) / ProShow and Powerpoint / Impress is that the later require either Powerpoint or Impress to run. PTE and Proshow produce executables that run on any Windoes based PC. You can also output to a huge variety of formats - including You Tube.

Either way, it can be a great way of displaying your images. However the same rule apply to these modern slideshows - as they did to 'holiday 35 mm slideshows of yesteryear.

Keep it short, I find 4 to 5 mins, is enough. Any more and folk tend to get bored.