Internet Explorer 8 and earlier can't download the webfonts that Old English Aerobics uses: runes and some other characters may not display properly. If you can't upgrade your browser (or don't want to), install the Junicode font and your display will look much better.
Does the floating dialog box make you queasy? Just drag it out of the way: it will stay wherever you put it until you either close it or double-click the title bar. If you want the dialog box always to stay put, uncheck “Dialog boxes move” in the Options dialog, which you can bring up by clicking the gear button.
When the dialog box is fixed in place, you can resize it by dragging the lower left corner.
Welcome to the home of the Old English Aerobics Anthology. The readings here are also printed in Peter S. Baker, Introduction to Old English, published by Wiley-Blackwell. You can get a copy here, here, or here, and you can consult much of the book for free courtesy of The Rawlinson Center of The Medieval Institute at Western Michigan University.