Originally Posted by joesixpack
You can, but it's not as important as the app freezings. ES File Manager should work just fine - I just mentioned Root Browser because that's what I'm used to.
This has worked great for me. So far, not a single update notification!
Thanks again. Just to let others know, merely freezing (via Titanium Backup) the 2 files that Joe6Pack mentioned (FWUpgrade.apk and SDM.apk) was enough so that my phone wouldn't keep bothering me that an upgrade was available. I didn't have to do the rest root browser/file manager stuff.