You should be OK. The main startup things to watch are automatic updates - Adobe's one is particularly obnoxious even without using the Creative Cloud manager. Updaters always seem to know when it's exactly the wrong time for them to pop up, and some are very persistent in their demands. Like Adobe's, which keeps resetting itself to "automatic updates" unless you keep an eye on it.

mettelus
Just check msconfig.exe regularly, especially after you use something that likes to load itself on boot. Adobe is the #1 offender of this. Setting priority of some processes to "manual" is also useful to keep them from autoloading (and can also knock the priorities below "normal").

Legitimate programs can be managed usually via the above and are non-issues for the most part.

 
This, imo is spot on.  Tho in Win 8.1 the program you use is Task Manager.  If you've never used it before, when open your Task Manger, you will need to click on "More details.  Then open the start up tab and you will see what is loading when you fire up your machine.  I personally have nothing in my start up enabled.
 
There are also "Services" but require a bit more knowledge to be tinkering with.

I built my current PC as a DAW exclusively but there are so many facets to using a DAW it became a real pain having to go back and forth between rooms to use a different computer to do word processing and other chores, considering that 95% of my computer efforts are DAW or at the very least, music related so I thought what the hell. Now I have everything on the one PC permanently hooked up to the net always powered on with never a problem in sight.
I use an iPad for most of my web stuff but it does complicate capturing images etc so for those times I need to work on my DAW. Even though my DAW is always connected to the net the only net activity I do is in connection with downloads and updates for music software or an audio related project. I never surf the net anyway but would never consider doing that on my DAW.

BUT having said all those things I don't just download trial software and freeware willy nilly. I'll do that on my laptop. Unfortunately the laptop carked it recently so I'm waiting to be able to get it repaired as its my learning programming PC.

mudgel
 it became a real pain having to go back and forth between rooms to use a different computer to do word processing and other chores.

Consider dual boot and/or virtual machines (don't run a DAW under virtual machine however).

Been there done that. No thanks. Not enough room on a 250GiG SSD for dual boot. I'm happy with the way it's setup and not looking for a change.
Besides apart from Video and audio programs and utilities the only software I would, could or should move is MSOffice 365.