The first thing I would do is backup what I've got on the SD card in my phone. Copy the whole thing to a PC or something like that.
Make sure you sync whatever apps you have to the cloud (internet, whatever). Such as your contacts, email, evernote, anything that you can sync to the internet or your PC.
Then make sure your phone is fully charged. You don't want to start rooting and flashing ROMs on a low battery.
Then, root your phone. It's very simple. Just follow these directions:
http://www.droid-eris.com/tutorials-corner/one-click-root-for-eris/Then I would download ROM Manager from the market, and install Clockwork Recovery. Clockwork Recovery is installed from within the ROM Manager app.
Assuming that you have backed up your SD card, I would wipe the SD card clean - format it.
Then use ROM Manager to back up your current ROM - just in case (but you'll likely never go back, unless you need to take the phone in for service).
Then I would read the install instructions for MacroDroid's MacROM from this link:
http://www.droid-eris.com/roms/macrom-mr2-cm7-1-0-v2-3-4-%28vanilla-and-ginger-glass%29/And download his ROM from this link:
http://forum.xda-developers.com/showthread.php?t=1038361Don't forget to not only download the ROM, but also GAPPS and whichever launcher you want (I use Launcher Pro) - they're linked on that same page.
Copy that ROM file (it's a .zip file) and the other .zips you downloaded (GAPPS and Launcher) to the root folder of your SD card.
Boot your phone into recovery mode and do a full wipe and a davlik wipe (do them both a few times, just to make sure it's all cleared out). Then flash the MacROM file - don't reboot when it's done - you're not done yet. Then flash the GAPPS file. Then flash the launcher file. Then reboot.
This reboot will take a while. Be patient. After rebooting, your phone will behave as if you just pulled it out of the box - asking you to setup your google account and all that business.
Set your phone up.
Download your apps.
Enjoy the AWESOMENESS that is Gingerbread on a Droid Eris with a great & stable ROM.
Of course, there are ways to back up your apps and your app data, if you have to. But that's a whole other post/subject. Doing what I outlined above, you'll have to reload and reconfigure all your apps. You'll also have to copy back from your PC any stuff you wanted on your SD card, such as music, movies, whatever.
What will you get by going through all of that?
* Significantly better battery life
* A faster and snappier interface
* The latest version of Android for phones, supporting all the wizbang stuff that it supports
* The ability to move apps from main memory onto the SD card, freeing up main memory and getting rid of memory warning messages and errors.
* A ton of features and config options that you weren't even aware of, and didn't even know you NEEDED.
