Well, you CAN install Vista from scratch. I did it about a month ago, when I decided to upgrade my Vista Home Premium to Ultimate. FWIW, it took me about a week, so I won't say it was absolutely painless, but ...
So you've got SP1 installed. Do this: Go to this site (the Microsoft Update Catalog) and download SP2 for Vista X86.
Right click, install as administrator, reboot. Look to what else you have on your system or might need. This is what I got from my initial installation and support packs, or dug up from the internet:
Dot NET 3.5.1
Dot NET 4.5
DirectX 11 (June 2010) and update
Internet Explorer 9
Visual C++ x86 & x64 2008
Visual C++ x64 & x86 2010
Visual C++ x64 & x86 2012
Visual C++ x64 & x86 2015
Windows Media Center
Windows Media Player
Note that's all Microsoft stuff. There was also about 50 utilities and hardware drivers to install. This was a homebrew desktop system, so I won't bother to recite the list; it'd be mostly useless to you. Also I did a bit of system tweaking -- assigning partition drive letters, changing font sizes, getting speakers to produce sound, getting two monitors to cooperate, and all that fun stuff. Anyhow, I got this far in about one day and keyed in the 25-character Activation Code, then clicked on the Send Request tab, Which got approved in about two seconds, instead of the half hour process of repeating letters and numbers I'd become accustomed to in Vista Home Premium setups. I damn near fainted from surprise. Instead I went to bed.
I spent about twelve hours the next day doing just about nothing because MS wouldn't give me any updates. Does this sound familiar? I got so bored and so antsy I started reading sections of the Bleeping Computers Vista Forum and other obscure websites, looking for hints or at least distractions, and finally came across Imacri's helpful suggestions. Which I had actually seen before, I hate to admit, and hadn't paid attention to because I wasn't in immediate need of such handholding. NOW, with a new setup I did need that help and I finally noticed it.
So. Go to the Microsoft Update Catalog again, look for Vista System Update Readiness Tool (KB947821) and download it. Update programs (those xxxxx.msu files) won't run in Vista SP2 while Windows Update is running. Turn off updates on your system, change settings to "never look for updates" and reboot and THEN run SURT. Then run those Speed UP patches, then reboot. Switch settings to allow updates, It took just a couple minutes for updates to start appearing for my system -- about 280 of them.
After that things were straightforward. On the third day. I started reinstalling the applications I'd had before, installed some more utilities and hardware drivers, fiddled around with antispyware and malware apps, etc. The details are unexciting. This will bring your system (mine anyhow) up to the mid April 2017 condition, where Microsoft stopped Vista support and cruelly cast us faithful users all aside. Never Forget, Never Forgive! Never Surrender!
Oh well. You can call it quits here. Aside from occasional utility updates, there's not much more to do. Depending on your enthusiasm for such tasks, you might consider updating Vista with patches for Win Server 2009 SP2. There are arguments for and against this, which I'll not bother to recite -- I'm kind of up in the air about this myself. There are sub-Forum threads for that topic here and at the MSFN Vista site, which you probably ought to leaf through to get some handle on what's involved -- it's a manageable task.
Good luck! Enjoy!