32-bit IE 9 is what you want to run, but Microsoft makes installing it on 64-bit Windows a little confusing so here's how to do it and what's actually going on.
First, as many of you have discovered, if you try to download and install 32-bit IE 9 on a 64-bit Windows PC, you’ll get the error message: “This version of setup doesn’t support your Windows system type (32-bit/64-bit).” It’s right. You can’t.
Read Full Story at ZDNET By Steven J. Vaughan-Nichols | March 11, 2011, 9:58am PST