Login problem after latest upgrade

[PJJ]

OK, I did it again - managed to create a major and unusual problem most will not encounter.

Neither one of the suggestions made in this thread does work. Reason: Read only file system.
I went into fstab and mtab and checked the entries:
fstab
# / was on /dev/sda7 during installation
UUID=c102d52b-a8f5-4030-b593-039d4efc1532 / ext4 errors=remount-ro 0 1

Changed that to: . . . errors=remount-rw.

Unseccesful, but complains about unrecognized system settings.

mtab:
#/dev/sda7 / ext4 rw,errors=remount-ro 0 0

changed to: /dev/sda7 / ext4 rw 0 0

Also unsuccessful.

Unless someone can tell me how to change the file system from read only to rw I am at the end of the rope.
Re-installation is difficult however, because my CD/DVD reader does not read DVDs for some reason. And the laptop does not want me to start it from a thumb drive.
I also have a card reader. Could that be used to create an alternative startup disk?

In fact, I am just now downloading the latest daily build of 13.10 to install it on a SD card (bootable). Hope my old laptop can handle it. If not, I will use the conventional way to brun and install from a CD.

Better than wasting more time trying to achive the impossible. File system remains r/o despite all attempts to change it.

Consider the thread 'solved' by abandonment and re-installation of the OS.

[PJJ]

OK, I am back on 13.10 (10.0.0.-generic).
Here is what happened. Maybe this will give someone a clue how to resolve a similar situation.

As mentioned I could not repair the installation because the file system was mounted r/o only.
All attempts to change it back to rw failed.

Therefore I used an installation disk with 12.04 on it to re-install the system - after backing up the data, of course.
After 12.04 was installed, I began a series of upgrades to finally end up at 13.10 after changing sources.list entries from precise to 'saucy'.
In the process I had to use many of the command suggested in this thread, mainly:
sudo dpkg --configure -a (did a lot of work)
sudo apt-get install -f (ditto)
sudo apt-get install dist-upgrade.

Followed by:
installing update-manager-core (which was already there) and
do-release-upgrade.

That prompted muon to announce a system/version upgrade. I took the suggestion and, voila, ended up with the latest version of saucy.

Problem solved!
For the price of a new installation, of course.

But that is fine with me.