It's an emulator! That plays old LucasArts adventure games, along with a handful of other similar titles. You'll still need the actual disks/CD, of course. Unless you want to play Beneath a Steel Sky, because Revolution Software provided the source code. Oh, and Beneath a Steel Sky is available as a free download from the site. The emulator also supports Simon the Sorceror 1 & 2, Broken Sword, and Flight of the Amazon Queen, which is also freely available thanks to John Passfield and Steven Stamatiadis.
Torchslasher had this sort of problem last year, and ths solution worked for him: I don't know why I have thought about doing it too; my wireless never stops working, but can be incredibly slow. 8 hours for the Madden demo!