Sorry to say, but no. To oversimplify, most Hollywood Blu-ray titles contain various forms of copy protection, meaning that you'll need a software player capible of unlocking the content to view them. There's also the navigational structure of the disk to consider, so even if you run a program like Any DVD HD in the background, you'll still need a specialized player to handle the full capabilities of the disk.
Let's also not forget the DVD drive; it uses a different reading laser than a Blu-ray drive, therefore can't read a Blu-ray disk.
On the other hand, if you're simply wanting to be able to view high-def content (movie trailers and the like), your main bottleneck (assuming you have the right codecs) would be your video card's ability to smoothly play them. That's because the streams normally aren't encrypted, and tend to simply be high-resolution .MP4, .MKV, .WMV or .AVI files.
Again, this is oversimplified--perhaps even to the point of not really answering your question--but these are a few of the obstacles you'll be faced with.