The 1half1.zip file you have requested: Media / Videos and Trailers / User Videos / April 2008 / Half-Life Video 1 - 4.04mb is not available. Perhaps try browsing all files for the game Half-Life and upload any files you want to share or are missing. This is the only information we could locate:
Gameplay from an early build of Half-Life. Shown are slippery floors, breakable glass and some headcrabs.