I use to do a lot of stripping-out of unwanted apps and turning services off..etc...back in my W2K and also in my XP DAW systems. There were extensive optimization procedures that people were doing.
With my Win7 DAW...I just run it lean by NOT adding more apps that I don't need...it's a DAW-only box, so besides the OS, the only other stuff on there are the audio apps, and maybe a PDF reader for the manuals, and that's about it.
I think I did some basic power setting adjustments in the bios, and just minor tweaks to suite my preferences, like I turn off the networking all-together, since it's an off-line DAW. I didn't much more than that...the rest is default.
That said...not adding lots of non-audio stuff makes a difference. My Win7 DAW computer boots 5 times faster than my Win7 work laptop, which has tons of shit on it, including all the anti-virus/anti-spyware stuff.
Many of those additional apps will load pieces into the background so that they appear to load faster when you want them...so they can suck up some of your resources, even if you have a robust system.
I just don't see a reason to have some non-DAW apps installed and their background services always running...if I'm never going to use them.
(Knock on wood)...my current Win7 DAW has never crashed/frozen...there's just not much there to get in the way.