I can't find an answer for this anywhere I looked, even in the guide. When you grab the blue dream stone from the obelisks, 10 or 12 harpies descend, force you into a corner and have their way with you. How do I keep this from happening, or if I can't, how do I keep myself alive?

The Witcher 1/2 are the only games in which a comment about harpies descending, forcing you into a corner, and having their way with you is truly ambiguous in meaning.

You'd probably have more luck asking on TW2 forum, as it's more active.

Should you maybe have posted this in the Witcher 2 forum instead of the general forum?

Edit: Wow, 3 people telling you the same thing at once.

There's a Witcher 2 forum here on GOG?
OK, Awesome! Posted it there.