Windows vista has turned on unnecessary features. You can get rid of some windows features, that you don´t need and speed up your vista.
Go to Control Panel and click on Programs and Features
Click on Turn Windows features on or off
After this will appear windows feature window. Here you can turn on or off every windows feature. Turn off those you don´t need. Below is list of features that you should turn off.
Games (If you love vista games (Solitaire,Minesweeper and etc.), don´t touch this)
Internet Information Services (support for web and FTP servers, necessary if you hosting websites on computer)
Microsoft .NET Framework 3.0 (this is for .NET 3.0 components, necessary if you are programmer )
Microsoft Message Queue (MSMQ) Server (technology enables applications running at different times to communicate across heterogeneous networks and systems that may be temporarily offline. Simple said ,useful only for programmers. Learn more about MSMQ on this link )
Print Services (Necessary if you are using internet printers)
Removable Storage Management
Simple TCPIP services
Windows DFS Replication Service
Windows Meeting Space