eyeball burning glare isnt normal in fallout 3
in game look at the sun and hold SHIFT and press F12, if it dissapears its because of the ENBoost
if youd like ENBoost on, but dont want to be blinded, hold SHIFT and press ENTER. you can change some ENBoost options (or do it through the ini files)
if your following the guide by the letter then you forgot to follow this instruction:
Go to the Fallout 3 goty folder and open enbseries.ini in a text editor (Notepad++ would be an excellent choice here).
Set the first line to UseEffect=false. Save and close.
with it set to true, on the default downloaded from the site ENBoost, you will be blinded. the graphics look nice, but you lose effects (start a new game, you dont get the blinded effects from birth so it looks a bit odd)