unable to install LR 2.5 ( the oldest version I still have) on to the Dell because I get a message that this OS will not install LR.
LR might be stopping because of the screen dimensions. On some netbooks it's possible to use an external monitor at 1024x800 which will fool LR into installing and once installed it will run on a 1024x600 screen.
There are also some other hacks around to fool software into thinking the screen's larger, Google is your friend to find these.
FWIW I've got LR3x to run on an XP netbook with a 1024x600 screen with little trouble and find it's hugely useful, although fast it isn't.
Other than that I'm sure someone will recommend a program that will copy to 2 HDDs, but I've never needed to so that.