Should I install a normal window or glass block?
Cost is also another major factor. Where I'm at you'll spend much more for glass block vs a double pane window, either picture or hung or sliding. Ease of installation is another. It is much much easier to install a window than to properly install glass block. You will need to ensure that you flash the exterior of the window or the glass block properly. Also, making the glass block and the window look correct from the outside is also much easier when using a window.

If it were me, and the aesthetic of the house absolutely didn't call for a glass block window I'd go with a standard window.