I have had a couple of Windows 7 machines display fonts incorrectly in
IE before. One example was everything was showing in italics. I
finally figured out the problem as a corrupt font file. If you have
another Windows 7 machine you can copy over the font file to fix it. If
not, maybe there is a way to extract it from the install CD's or
something. But, it is probably a corrupt font file for whatever your
default IE font is.
Jeff