I have some raw files from my camera (.nef files) that nI used the free Adobe dng converter to convert them to.dng files. How do I get the dng files to load into lightroom 4?
You Import them using the Import button in the Library module.
LR does not Open Images files like some other Image Viewing programs. LR is a Database system and to view images in LR you first need to import them into the LR Catalog file.
Please review these tutorials to become familiar with how LR works and how to work with LR.