Oh this is a fun topic. Which to choose from, HD-DVD or Blu-ray...
My money would be on buying a PS3 with its Blu-ray disc player and just play games on it (duh). For $400 you get something that costs around $3000 in Japan right now. Of course prices will drop severly once they go into mass production for the PS3 and other companies and the adoption of the HDTV into the mass market (prices need to drop atleast half their current price). Still you cant go wrong from getting a Console comparable to a PC and have a Blu-ray player.
The problem with Blu-ray is that it requires a whole new manufacturing process and, this is not as well know to the public, that the Blu-ray discs will only have a .1mm layer of protection between the whatever is being read and the surface. Sony and it's minions realized that scratching would be a major problem because even the tinyest scratch would damage the code. They have a solution but at a great cost ($5.00 a Blu-ray disc). Its basically like a miny armor that is put onto the reading side of the disc, the armor is suppost to be somewhere around 20x more scratch resistant than a regular CD/DVD.
HD-DVD requires very little new manufacturing to create movies/games. It can be used in every household that has a DVD player, and uses current technology. The drawback is the capacity. It holds something like 15Gig on a disk, little compared to the 25Gig of the Blu-ray (single layer). But there is hope. Toshiba or whoever is sponsoring HD-DVD apparently has a solution. By using a dual layer disc, they put 30Gig on the dual layer side, and then another single layer on the other side, giving it a total of 45Gig. This reading process would also require you to only switch the sides of the disc to get the extra info, or if there is a player with a laser on the top and the bottom, there would be no stalling in the disc reading.
So all bets off, I will withhold my oppinion on which one will win the next gen DVD war, seeing as how both of them are so strong and only one can come out a victor.