Many thanks for the links.
These and other links referred to helped me to reduce the size of Windows 7.
Luckily it turned out to be very easy. I
- downloaded and installed the free disk frag program (aus) from www.auslogics.com (very good and shows allocation diagram)
- first ran the W7 defrag function and this reported 8% fragmentation (but no diagram).
- ran aus 'analysis' function which showed space allocated at the end of the w7 partition stopping any reduction in size.
- defragged by aus. No effect. There were still blocks allocated at the end of W7 partition.
- defragged by w7 again and then defragged by aus. This time I managed to reduce the W7 size! Don't understand why it did not work the first time.
I could have reduced the size a bit more, but stopped and installed Ubuntu 12.04 and restored my data and programs from backup dvds. Ubuntu ran extremelly well.
I don't know if I could have repeated the procedure reducing the size of w7 a bit each time. Anyone knows or willing to try? Of course before adding Ubuntu in case W7 would suddenly hang and need a restore.
W7 disk management only allowed a reduction of size to about 50%. Would it insist on having 50% of 1TB or 2TB disks too? That would be intolerable if you only need a small W7.
P.S. attaching the gparted display after the Ubuntu 12.04 install.