Tutorial 1 – Installing Themes in Vista Using Tune Up Utilities

Step 1 - Download and Install Tune Up Utilities from ->Here<-

Step 2 – Open It and click Customize Windows (at Left hand side)

Step 3 - Click Visual Style ( Botton of Left hand Side)

Step 4 – Now Click on Add > “Install Visual style from File”

Step 5 – Choose the Visual Style ( .msstyles or .theme format ) you had downloaded from your Hard Disk.

Step 6 – Click on “Apply Visual Style” to make it work.

Tutorial 2 – Installing Themes in Vista By Patching Uxtheme Patch

Download This Pack Of Software & Patches which you Need to Install Themes in Vista SP0 & SP1-

Click Here To Download

After Downloading , Extract the Folder and you will Find Take Control , uxtheme pactches for Vista SP1 and SP2 both for 64 & 32 bit Vista .

Open Take Control Folder , Right Click it and “Run As Administrator”. Now Go to Add , Browse to C:Drive > Windows > System 32 and select Uxtheme.ddl , themeui.dll , shsvcs.dll , Open Them and Hit “Take Control” . This will help you to edit those files easily & rename them .
Now go to System 32 and rename those files to Uxtheme.backup , Uxsms.backup , shsvcs.backup respectively .
Now Go to Downloaded Folder and open the patch compatible to your Vista ( For Eg if you have Vista SP0 32 bit then open – ‘Patch Vista SP0 32 Bit’ ) . Copy all those three dll files to system32 folder .
Restart Computer before using any Theme (Important) .

Now You can use any themes  or Visual Styles by Copying   to c:\windows\resources\themes .

You are free now to use any Vista Theme or Visual Style in Vista .Please Give Feedback Of this tutorial . Hope this tutorial will help you  .