How about an OS that is supported to do modern stuff on modern hardware.
On a desktop or Laptop that would be; Burn a HD Bluray disk, Play a fully featured game released last year. Encode a Bluray DVD to a HD MKV file for your HDMI HD Media player in 10 minutes. Home studio quality digital recording, Surf quickly and painlessly. Make a good quality 2 hour home movie in an hour not 2 days.
For a tablet: Ummm Play PACMAN?