SharePoint 2007: Where to look for SharePoint version?

[What you have]:
The SharePoint 2007

[What you want]:
You want to know the current version of the SharePoint

[What you want to know]:  

Here are several ways to find the version  out:

1. Central Administration - Site Settings - Version

2. Central Administration - Operations -Servers in Farm - Version

(or Version column in the row where SharePoint Server resides)

3. PowerShell command (Here is a quick intro : "SharePoint and PowerShell"):

<#
.SYNOPSIS
Gets the sharepoint version based on the "hklm:software\microsoft\shared tools\web server extensions\12.0" key
.DESCRIPTION
Gets SharePoint product version from registry and from details info from microsoft.sharepoint.portal and Microsoft.SharePoint
.EXAMPLE
Get-SPVersionV3
.NOTES 
More details on how to retrieve version http://sharing-the-experience.blogspot.com/2011/05/where-to-look-for-sharepoint-version.html
AUTHOR: Natalia Tsymbalenko
BLOG: http://sharing-the-experience.blogspot.com/
#>
Function Get-SPVersionV3
()
{
$dlls = @((Get-Item "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\ISAPI\Microsoft.SharePoint.dll"),(Get-Item "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\ISAPI\microsoft.sharepoint.portal.dll"));
$dlls|foreach{ Write-Host $_.VersionInfo.ProductName " : " $_.VersionInfo.FileVersion };
$registerValue=(get-item "hklm:software\microsoft\shared tools\web server extensions\12.0").getValue("version");
Write-Host "The version in windows register :$registerValue"
}

Get-SPVersionV3;

4.

Run SQL select command against your "SharePoint_Config" db:

SELECT * FROM [dbo].[Versions] WITH (NOLOCK) 
ORDER BY Id DESC. The top record shows the current version applied.

5. For MOSS:

- go to Microsoft Shared\Web Server Extensions\12\ISAPI;

- find microsoft.sharepoint.portal and Microsoft.SharePoint.

- properties -> Details -> file version

If you noticed difference between two files that means that you installed update for Server but forgot (or didn't know) that you need to install WSS update also.

Windows SharePoint Services continues to remain separate and is not included in the Office SharePoint Server package.

Recommended installation sequence for updates

The latest service pack for Windows SharePoint Services
The latest service pack for Office SharePoint Server
The latest cumulative update for Windows SharePoint Services
The latest cumulative update for Office SharePoint Server

Note: Microsoft enforces the installation order of service packs, but does not enforce the installation order of packages or patches. You can install packages or patches in any order you want, so long as every server in your farm is updated to the same level when you are done. I

6.IIS

-Sites->SharePoint Central Administration v3 -> HTTP Response Headers -> MicrosoftSharePointTeamServices

7... and one incorrect way- Programs -Programs and feature -Uninstall or change a program

 - version . For some reasons it shows not the current version

If you are more visual - you are welcome to scrutinize my comparison of the farm version 

from different places:

  

[What you want to do]

My recommendation is to use the PowerShell function Get-SPVersionV3. Here is a quick start with PowerShell PowerShell and SharePoint: What, Why and How

What if SharePoint Cumulative Update: version won't change ?

[What you want to consider]:

By the way, here is  up to date info about current version