mathews2010

Vista sp1 via windows update
Windows Vista SP1 RC Refresh 2 6001.18000 Released - Include WU Install Registry Code » My Digital Life

vista sp1 standalone packages
Vista SP1 RC Refresh 2 6001.18000.080118-1840 Standalone Offline Install Package BT Download » My Digital Life

it might help clean away some junky corrupted files
http://www.vistax64.com/tutorials/131758-speed-up-computer-boot-time.html

hope this helps