Vista Service Pack 1 question

Hello, I am M Sullivan, II
I am having problems re-installing service pack 1 on my computer. I am currently running Windows Vista Ultimate Edition. I removed Vista Service Pack 2 and Service Pack 1. Just to install my copy of Visual Studio 2005 Standard Edition. I was able to install Visual Studio 2005 and the ENU service pack 1 for Visual Studio. I am a little lost on why I am having a internal fatal error 08x000FFF, which is an Internal error during the middle of the installation process of service pack 1. I also tried to go to safe mode to install service pack 1 for vista, but I still get the same 08x000FFF error message. I have also tried to UN-install things off the computer to help the service pack 1 to install again. I haven't yet UN-install Visual Studio 2005 ENU service pack 1 yet. I am a little lost on the sequence of doing this. I remember there were certain ways to get things done on Vista, But for many years until now I used my Windows XP Pro to support my computer needs. Windows Vista Ultimate runs a little slow on a computer. It was design to be for workstation computers. I build one and can say it was great having all that power. But I only build it for 3dStudio Max. Sorry I got off topic.
Any input would be grateful. I have lost some of my knowledge on Vista answers and procedures but I have memories of other things that will be helpful to someone else. Thanks for reading my post and any help is gratefully appreciated.