Argh, I just beat my head against a wall trying to do this for the last couple hours:(. After a bit of web searching, I finally found this. So if you try to run the SQL Server 2005 installer to install the full version of SQL Server Management Studio (SSMS), you will inevitably get an "Edition Version Conflict" message. However, the installer sends you on a wild goose chase because it just tells you to uninstall "express tools." I did what I would guess most of you would do. I uninstalled SSMS Express. Then I ran the full installer again. DOH! Same error message (head banging began here). Turns out that you have to do the following (pasted from the link I provided earlier) after you uninstall SSMS Express:
"1. Click Start, and then click Control Panel.
2. Double-click Add or Remove Programs.
3. In the list of installed programs, click Microsoft SQL Server 2005, and
then click Change.
4. On the Component Selection page, select Workstation components, and then
5. Click Next.
6. On the Change or Remove Instance page, click Change Installed
7. Click Client Components, and then select Entire Feature will be
8. Click Next.
9. Click Install.
After that, please rerun the setup wizard and then check if the SQL Server
Client tools are able to install on the system."
Hopefully this tidbit prevents someone from banging their head! Unless, of course, you are a Metallica fan:).