I am using a 15" 2.4GHz MBP for my mobile photo need, with a LaCia 160GB Rugged HDD, running on Leopard. I use Aperture, which handles my RAW files with ease, and export them as TIFF/JPEG as finalised version. As Aperture does not alter your original RAW file no matter now much adjustment u did, it give u peace of mind, exp on road knowing that u can always have the original back at anytime.
As on your question on slides show, there are a few options that u can explore when using Aperture:
(1) Slides show native from Aperture, with customizable back ground music and transition.
(2) With Preview in Aperture enabled, the same photos can be used in iPhoto, which come pre-installed in all Mac. iPhoto runs impressive slides shows, with great transition and music from your itune library.
(3) You can also run the slides show from Front-Row, where you can control it using the remote control that comes with your Mac.
(4) Optional: I also uses Fotomagico, an impressive slide show program that allows u full control how the pic are to be presented, and how each transition is done, back ground music etc with ease of use.
All these can be done on either your LCD Screen, or if u like, on any wide screen or regular TV via the DVI port, making presentation easier.
I guess all these can be done on a PC as well, but in my opinion (very biased as I am mac user since 1989, hee hee), Mac integrates the many software together much better (iLIFE). And since u shoot in RAW, u sld really try out Aperture, as it is fast, easy and intuitive.