How do I open a ROM file?

Solution: Use File Magic to Open Your ROM File

in the program or device for which it was developed), you might be able to open it with a universal software viewer. Depending on the exact file format, you could use a universal software viewer such as File Magic [download] to open your ROM file.

How can I legally use ROMs?

Emulators are legal to download and use, however, sharing copyrighted ROMs online is illegal. There is no legal precedent for ripping and downloading ROMs for games you own, though an argument could be made for fair use.