Sometimes you can just rename the .VRO file to .VOB and have it work, but it usually doesn't. From what I remember .VRO is a transport stream, so different than a regular .VOB file. A couple years ago I used a program called VOBTool and a PC drive that could read/write DVD-RAM. I renamed the .VRO file on the RAM disc to .VOB, then used VOBTool to extract the video from the .VOB file.
There is an old post on the subject here on CDFreaks somewhere.