It could be that your graphics card is not Vista compliant.
Could you make sure you have all the latest updates for your machine, by clicking on:
http://windowsupdate.microsoft.com
You could also check on the graphic card manufacturers website for any updates.
Alternatively, you could use the software cursor available in Stardraw which is selectable from the Options->Preferences->Cross Hair Cursor. David SnippStardraw.com Ltd