I finally took the plunge and upgraded my debian box to testing, also known as 'wheezy' which is the next version of Debian. I changed my /etc/apt/sources.list so that everything that said squeeze was changed to wheezy, and then did a 'sudo aptitude update' and checked that every entry was for wheezy. Then I did 'sudo aptitude dist-upgrade' which wasn't a good move really as aptitude couldn't complete the operation so I had to resort to 'sudo apt-get dist-upgrade' which finished it all off. Then a quick prayer and reboot.
The first change I noticed was that I got a grub menu showing all my choices of kernels to boot from, and then into the login menu. I chose 'gnome-classic' as being the nearest to gnome2 as I knew that I did not like the gnome3 setup. Then installing vnstat, which was automatically started, rysnc, logwatch, ntp and krusader. With the aid of krusader I was able to copy across my backup to my desktop so I had all my documents etc again.
Gnome-classic was okay but I never saw the menus in the top-left of the screen, they were always too dark so I navigated it by instinct and knowing what should be there. I didn't find anyway of making the screen lighter, so in the end I installed XFCE, and logged into that. Ah, I could see the desktop and navigate about it nicely. Using 'alacarte' I was able to add menu entries for firefox, thunderbird, nautilus and truecrypt, and now I was in business again.
Truecrypt didn't install out-of-the-box, I had to google a solution which involved dropping down a version, which then installed to the /temp directory, from where I could copy the various bits of the programme over into my /programmes directory, and setup truecrypt to be used in daily usage.
I feel that XFCE is the desktop environment for me on my aged hardware, and is easy to use and navigate about too. Having gnome installed also meant that I could use their programmes under XFCE too. Knowing that Wheezy is going to be released with XFCE as its default desktop environment in place of Gnome3, I feel that I'm getting to grips with the next desktop. I've now been running wheezy for about four weeks, updating it everyday with the released updates and, so far, with no problems from running 'testing'. It seems to be rock-solid and stable, just like debian as a whole, and I'd recommend it to anyone who's linux-savvy to try out.