The table in our entryway is a sea of picture frames...different sizes and different colors, but all depicting wonderful memories. I print all of the photos myself so that I can change them out often. You don't need to use photo paper to get a good print. I prefer to print on cardstock (found at any office supply store) because photos will buckle in frames if they are printed on regular copy paper.
I like to take very close-up photos. Of course, that doesn't always work (especially when kids are involved!); often I have to crop the photos to achieve the desired result. This can be done with a variety of computer programs. I always use either Microsoft Publisher or Picasa, a fantastic free software that allows you to organize and edit your photos and then publish them to a free website for sharing with friends and family.
Photos in frames should be as close-up as possible. You want to be able to see who is in the photo without having to go over to the frame. Many times people make the mistake of thinking you have to see a person's entire body in the frame. Sometimes it's more desirable just to see faces! I usually print one size bigger than the frame opening for all of my photos. Doing so brings the subjects much closer and removes any unnecessary background in the photo. For example, for a 4 x 6 opening, print a 5 x 7 photo and trim it to fit. For a 5 x 7 opening, print an 8 x 10 photo, and so on (note: this will work about 95% of the time...sometimes the photos are too large).
The frame in the above photos has a 4 x 6 opening. In the top picture, I printed a 5 x 7 photo and trimmed it to fit. Contrast that with the bottom picture, which has a 4 x 6 photo. The top photo brings into focus what is really important in the photo (in this case, my mom and me!) and eliminates the unnecessary background.
Do try this at home! Happy framing!