Should not be difficult at all. Linux distributions, such as BT, will co-habitate with Windows. You will want to manually configure your partitions. Your options are to either deflate the Windows and Suse (root) partition and install BT in the free space or wipe the Suse partition and install BT in the free space.
The worst side effect, assuming a successful install, would be needing to manually configure the grub configuration file to remove the Suse reference if you wipe it out, but the install should take care of that too.