Windows Vista has built in Vista Updates downloader however it misses several features like letting user to save updates files, modify these updates files as per their requirement or letting users to download Vista Extras and other add-ons.
Here is one Free utility Vista Update Downloader v1.8.1 (VUD) Alpha toolkit from WinCert.net developed by Legolash2o, which provides several other features over default Vista Updater.
Features Provided by Vista Updates Downloader v1.8.1 Toolkit
1) Download Windows Vista Updates, Service Packs
2) Download Language Packs, Extras and Ultimate Extras
3) Download Feature packs, Tools, Driver Packs
4) Download Office 2007 Service Packs and Office 2007 Updates
5) Manage Updates Download Queue
6) Request Hot fixes
7) Built-in Add-on Integrator and Add-on Installer
8 ) CAB Retrievers from downloaded Update files
9) Built in Language Pack Converter 2.0 and MSU to CAB Converters 2.0
10) Update Integrator and Windows Image Mounter (WIM)
Screenshots of Vista Update Downloader v1.8.1 (VUD)
Vista Updates Downloader toolkit is still under development and there are several other features going to get added. Their might be some bugs in Vista Updates