How safe is the upgrade from 7.04 to 7.10?

[Liam Proven]

I have a fairly hacked-about with 7.04 system. I have nonstandard
apps, like Pidgin from getdeb.net. I used Automatix to get multimedia
support. Stuff like that.

It's showing its age. When I boot, it drops into a bash shell as it
starts the init process, saying that the error is that apt-get is not
installed. I can't use ^d to exit this, but if I type "exit" and hit
Return it continues booting normally. Yesterday, my 2nd monitor
stopped working, and occasionally, the PC has started freezing.

I have tried to install a 2nd system alongside my current one, but if
I try to install from the desktop liveCD, the installer hangs when
installing packages. The alternate CD crashes out with an error when
installing packages.

So I am a little reluctant to try to do an in-place upgrade on my only
working OS!

Is is possible and relatively straightforward to copy my root
partition onto another volume, so that I have a backup copy, and then
try upgrading one of them? This is already a multiboot PC: I have an
80GB disk with a 2GB FAT16 C: drive with DOS, then an extended
partition, containing, in order, a 4G W2K partition, a 4G XP
partition, a 4G spare Linux partition, an 8G Ubuntu root partition, an
8G Linux home partition, and the rest of the space given over to a big
shared FAT32 drive. There's a 2nd 10G drive with dedicated swap
partitions for Linux and Windows.

If I move stuff around to make space and copy my root partition into
the spare Linux partition, how can I be sure that it's loading from
the new partition only and not getting confused and getting bits from
its original volume? Is it possible to hide a partition from Linux in
the same way that one can hide partitions under DOS, NT and OS/2?

-- 
Liam Proven • Profile: http://www.linkedin.com/in/liamproven
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