Why is Sony Vegas taking so long to render?

I'm using SV pro 9. I'm rendering a 7min 30sec video. I did a few adjustments to improve video quality like brightness,sharpen etc. I go to render it I believe WMV 11 MPEG and it comes up saying it'll take 13 hours!! Is this normal? If so could anyone tell me how I could speed up the process without affecting the quality? Its been an hour and its at 6%. Please leave me an answer thanks!!!!