Is the gap between the wall and sub floor going to effect my laminate installation?

After removing the original carpet, I have found an uneven gap (between 1/4" & 1/2") between the sub floor and bottom of the wall board. What is the recommended fix for this? The gap is fairly deep and seems to go to the frame of the house. Should I fill this with something? I also cannot get the spacers to stack up. PLEASE HELP. It is for my nursery.