Here's the solution I could find for my Acer 5920G to go back to first day status, after trying couple of different methods:
Case: Notebook had initially Windows
Vista Home premium. While trying to install another operating system, notebook happened to be not booting, ALT+F10 was not working, harddisk was not formatted therefore recovery partitions still exist.
Step 1: Go to
http://gparted-livecd.tuxfamily.org/ and download live CD and write iso to cd. This will create a bootable disk with own operating system (Fluxbox) and partitioning software (Gparted)
Step 2: Go to BIOS of notebook (F2 at startup) and disable D2D recovery (I'm not sure if this is necessary but I did so)
Step 3: Change boot order in BIOS to make CD-ROM as first boot device.
Step 4: Insert your cd and boot the notebook using the CD. A partitioning program will appear when the CD runs properly.
Step 5: Identify your recovery partition (about 9Gb in size and mostly full), use change flags and mark as "boot". Some methods suggest to "unhide" the partition but this software does not show the recovery partition as hidden, I didn't change it but just marked "boot".
Step 6: Shutdown the application, remove the CD and boot.
Step 7: Since you have choosen recovery partition as boot partition the Acer recovery system will start and ask if you would like to return to factory defaults. By doing so, you'll have a clean installation of the original operating system you've received (Windows Vista Home Premium for my case).
Step 8 (Optional): After the recovery is complete, system automatically sets new Vista installation as boot partition, therefore you don't need to change it again. Optionally you may enter to BIOS and change boot sequence to make harddisk as first priority instead of CD-ROM.
Step 9: Enjoy (hopefully) your working notebook and plan about creating recovery CDs sometime (I'm not sure how the recovery CDs will work as I've seen many people complaining about them).
Regards,
Ilker Ustuner