I'd really like to find a way to reset my phone to the way it was when I bought it, like before I customized it. Is that something that would be possible?
Provided you haven't rooted your phone or changed the kernel, a simple Factory Reset will do what you require.
- Tap Settings.
- Scroll down and tap Privacy.
- Tap Factory Data Reset.
- Tap Reset Phone.
The steps you will have to take to restore to original state (Stock) if you are rooted
- Unroot using z4root (if you are rooted)
- you may not even have to do this with flashing the stock rom.
- Download the Stock ROM for the Defy
- You will need RDSLite to flash, and AFAIK, you can only flash the UK version as 2.51 builds cannot downgrde. You will need to search the internet for RDSLite as it is a proprietary software used internally at motorola.
- extract the zip so you have an SBF file
- Get the phone in the bootloader
- plug in the phone to USB
- open RDS Lite and browse for the SBF file
- Click on the defy and click start
You can probably find more detailed instructions, but this is the "basics" on doing it.