I don't know of another way to get the files off, though I didn't have to dig into it further. I'd expect that rooting a phone that won't boot is likely quite difficult, but I don't know.
The freezer trick worked for me for a while. But just before mailing it back, I was about to do a factory data reset to wipe it, and it rebooted again. That was it, I was not able to get it to boot up again, even keeping it in the freezer for a while.
So cold can help, but even if you can it running, the clock is ticking. Get your data off quickly.
The experience has motivated me to try and keep most of my data (pics, etc) on the SD card, if possible.
My replacement from Verizon looks like probably a refurb, since the serial number starts with 505. So it's an early production unit. I have no idea if it already has the bootloop fix, or if it's also a ticking time bomb.
Google's app & data backup/restore didn't seem to do much for me. It put my apps back, but the ones that I checked did not have my data. Then I restored my LG Backup file on top of that, and my apps had their data once again. So that was at least a big help.
I really like Android, but I freely admit that phone backup/restore is an area that could use a LOT of work.
My wife just upgraded her iPhone to a new model. She backed it up to iTunes on her laptop, then restored that to the new phone. Done, she has everything. I spent MUCH more time trying to get a backup that could go from G4 to G4, and it still missed some stuff.