I have installed SuSE 9.3 Pro on my harddisk. I have following partitions:

/ root 15GB
/ usr 2.5GB
/ home2.5GB
/ swap 2.7 GB

/dev/sda5 6757 8714 15727603+ 83 Linux --- root
/dev/sda6 8715 9041 2626596 83 Linux --- usr
/dev/sda7 9042 9368 2626596 83 Linux --- home
/dev/sda8 9369 9725 2867571 82 Linux swap / Solaris --- swap

I have a lot of space on my root partition as the programme has installed itself in my usr directory. Now 92% is used of it, but I would like to make it bigger (by taking from free space from root). However, in YaST it does not work, as you cannot resize partitions that are mounted...

Can anybody help me with this?

maybe try using a boot disk such as knoppix (I like the old gentoo one because it loaded quick as it booted into a shell instead of x). Be warned that resizing may wipe all data! It is worth making a backup before resizing the partitions using say fdisk.