Hi,
When you install any version of Vista, she likes to drop her boot files in the first partition ( this is the one that is on the left in Disk Management ).
The Vista o/s will then install on the partition you selected ( which will only be the same one as the boot files if you selected the first partition ).
Since you want to have only Ultimate installed do a clean install of Ultimate.
Clean Install with a Full Version of Vista
During the install you should format both partitions ( in step 11 of the tutorial - if you only want 1 partition delete the second partition - the one listed at the bottom ).
Highlight the first partition ( the top one ) as the partition to install Ultimate. (obviously if you have made it into one, just install on that ).
When the installation is complete, Vista Home will gone, and the partition you have installed Ultimate on will be
C: (System, Boot, Pagefile, Active, Crash Dump, Primary Partition ).
SIW2