It depends on how the picture was taken? What resolution? What megapixel is your camera and did you shoot at the highest resolution? How large do you want your print? Screen resolution and print resolution are very different. I could view a print on line at 72dpi and it would look great. Don't try to print at that resolution tho. It would be best to print at 300dpi but I've been pleased with 5x7s at 250dpi. Walmart digital printing (on line) will warn you if you try to upload a photo and print at a size and resolution that's less than optimum.
Monica

I have had enlargments done at shutterfly.com and kodakgallery.com and they came out very nice -- as monicakm said, they will let you know (with a little warning message) if the resolution isn't good enough for the size you want. I have gotten enlargements up to 16x20.

I've been using 4 megapixels. I usually print them out on my own printer at 200-300dpi. Either way they usually look fine. But, I don't have the capability to print out enlargements myself so will check into some of the places mentioned. Thanks!

Look around locally, there may be a digital printing store near you that will have better equipment than places like Walgreens, where a knowledgable person is checking input into the printer rather than a clerk just processing mindlessly whatever is put in. Some camera stores may offer this, otherwise look for a photo processing lab, most do digital as well as film.

In addition to enlarging the photos, you probably want them Photoshop enhanced a bit. My husband does this as a business (not advertising his services) and he says the bigger the end photo, the more important the corrective services.

In addition to doing the printing in-house, he sometimes sends them out to Costco for printing.

To Graywings:what kind of business does your husband do. I am a stay at home mom and need something to make some extra money.

I have a 5 mega pixel camera and I used Walmart photo and had enlargements made of my cats. I chose the smaller poster size (11x14) and they came out really nice. And they were very inexpensive as well. You can choose to upload slower and it will make a better image.

Thanks everyone! With my images, I think I'm going to be limited to something around 8X10. I found a way to do "photos to art" on Art.com and really wanted to this. I thought my caribbean photos would look awesome. However, the images need to be at least 2 megabytes and mine were not that high. So, I'm going to do smaller reprints and have to consider a new camera now!