Help Quality of pictures from computer to print
 

Hi all, Please help I have booked a few shoots of a party and baptism comming up and I have a problem, my phots after being saved on a CD are printing not the best they look a tiny bit pixelated or grainy its not huge but enough to bug me about my quality. I have concured with a friend who has the same camera and its on the highest quality setting with 10mp I have the canon xs rebel... She thinks it might be because I use free programs to edit my photos (I do unique edits and basic ones) she said that maybe running the quality. Another person said maybe the pixels or DPI of the photo cus mine seemed low. How do I fix this before I have these jobs and is there a program that if I want to edit I should use so that it doesnt mess up the quality. Please help I want them to be able to print what they see on the screen and see the same thing on the paper. My regular email is idontknow97@yahoo.com I am ready for your suggestions thanks.