1. Windows Vista Starter: This is for entry level users and limited in many ways.
2. Windows Vista Home Basic: This is suited for entry-level Home desktops and Mobile PC users.Windows Aero feature is not present with this edition.
Windows Aero let you preview your open windows in three-dimensional stacks, as well as taskbar buttons with live, thumbnail sized windows previews. It is an enhanced visual experience of windows.
3. Windows Vista Premium: This edition is the preferred edition for Home desktop and Mobile PC users. Windows Aero feature is present with this edition.
4. Windows Vista Business: As name suggest, it is for Business desktops and mobile PCs. Windows Aero feature is present with this edition.
5. Window Vista Ultimate: This is best suited for small office users. Windows Aero feature is present with this edition.
6. Windows Vista Enterprise: This is for large enterprises and organizations and available to Microsoft Software Assurance customers only.
There are 3 upgrade paths currently available within different editions of Windows Vista.
- From Home Basic -> Home Premium or Ultimate
- From Home Premium -> Ultimate
- From Business -> Ultimate
Link: Compare Windows Vista editions