Froyo was a huge leap. In my humble opinion, it should almost have been 3.0, not 2.2. I really can't speak to unlocking a motorola phone, as the steps would be different that on the nexus, which was remarkably easy. I'd have a look over at xda-developers, androidforums and at cyanogenmod.com for instructions on doing the install on your phone (whatever it may be). Some very knowledgeable people over at all three.
I honestly don't remember all the updates in froyo, since it's been a bloody long time since I've used any variation of eclair (2.1). Have a look at the froyo keynote speech (should be on youtube) for an explanation and demonstration of all the benefits (and a few nice apple jokes). For me, the addition of the wireless access point is enough on its own to merit the upgrade. That said, if you're going to void the warranty anyway to install froyo, if cyanogenmod is available for your phone, I'd grab the latest stable version of that rather than the stock version.
Thanks Mikey. This is what I found and was thinking of changing to it http://www.mydroidworld.com/forums/...ur-motorola-droid-rooted-users.html#post12906