Need to move everything from OMV drive to new drive

I have been scratching my head for a while here...

I have some problems with my computer that is running OMV. I would like to copy all the files from my OMV storage drive (2 TB disk) to a new disk. I was hoping that I could use Ubuntu for this, but I ran into permission issues...

I can still boot up the machine running OMV, but it is very unstable because of some hardware issues. Could I boot the machine and change the ownership/permissions and then plug both drives into another machine running Ubuntu, and then copy the files?

Or can I do something else? I'm really not sure what to do here (sorry for this rather stupid question). Thanks in advance!

I ended up giving up and transferring the files via the network (used a cable). It took a while, but now it's done. I need to take a look at that machine.

Thanks for your reply.