"My question is: Is it ok to sit the front speakers on their side or would that affect the sound distribution pattern and hurt the sound quality?"
Your ears will have to decide. It is, really that simple.
I just purchased my first surround sound speaker system (Onkyo SKS-HT510 based upon CNET's reviews) and am installing it in my living room...a very small living room. On the back wall of the living room I have an entertainment center with the TV and my stereo system. My center speaker is above the TV. The problem is where do I put the Front Left and Front Right speakers. I have bookcases Just to the right and left of the entertainment center. There is no additional room beyond the bookcases. So I have two choices for front speaker locations. First, I can put the speakers in the bookcases. But, since the speakers are 17" tall, I would need to turn them so that they sit on their side instead of their base. Or, I can make speaker stands and sit them in front of the bookcase (not really what I wanted to do since that would block the bottom 3 shelfs of the book case). My question is: Is it ok to sit the front speakers on their side or would that affect the sound distribution pattern and hurt the sound quality?