Originally Posted by Sharkonwheels 
This LR or LR2?
I have LR2, and when I open a DNG from the library, it doesn't do anything automatically.
Sure it does - like any RAW processor, it has to convert the image from its original RAW state to RGB so you can see it. In so doing, it is not only perfoming Bayer demosaicing, but also applying some sort of preprocessing exposure curves and white balance / color interpretation. That's quite a bit of work it does automatically.
Now, whether the hot pixel removal is part of this process I can't say for LR2 I can't say.