Hi. I'm DPI ignorant. I have a small photo (1" X 2"). I want to make it 5" X 7" but every time I do that, I lose the integrity of the photo. It becomes "blocky". I assume this has something to do with the dpi (maybe?). Is there freeware to convert a photo from very small to larger and keep the photo smooth and original? Or can someone give me dpi settings for a 5X7 photo?

TIA