Hello. I found a solution that worked great for me.
Download NextGen version 1.7.0 (see "Other Versions" @ the WP NextGen plugin page if you don't have it already somewhere archived). I have the latest version (1.7.4) installed on my WP database, and when I replaced the 'ngg.slideshow.js' and 'ngg.slideshow.min.js' from my current version with the corresponding files from 1.7.0 it fixed my current issue.
In my case I was uploading the two files from the local, extracted "nextgen-gallery.1.7.0/nextgen-gallery/js" directory to the remote "/wordpress/wp-content/plugins/nextgen-gallery/js" directory.
Hope this helps you! I read that some experienced image distortion with this fix, but so far in IE 6.x and IE 8.x it works fine for me. No need to reinstall NextGen, just find the older versions of these two files only and voila!