I need help with my settings when sending LR4 out for printing. I sent to costco that I have used for years and the colors were way off. My operating system is Windows 7.
First of all, your monitor needs to be adjusted properly. Whether you choose hardware calibration or not is your choice, but it is generally considered to be the best. If you have a printer at home that you can do a test print, and that print matches fairly closely, then you should be able to expect good results from Costco. Costco provides profiles that you can download that will enable you to soft proof using their settings. As far as export settings are concerned, these are what I would recommend:
Quality: at least 85%
Image format: JPEG
Color space: sRGB
If you are concerned about file size for uploading you might want to resize pixel dimensions. The PPI setting really has no effect on print quality. It's the pixel count that matters. For instance, if you are ordering 4 x 6" prints and you want 300 PPI then you would want pixel dimensions of 1200 x 1800 pixels.