Mike, your problem may be W8's search indexing, if you turn that off, access to files is dramatically faster.
http://www.addictivetips.com/windows...-in-windows-8/
Another thing to look out for is links to networked resources, I'd be suspicious of any dropbox links for starters.
If you started with 8 then upgraded to 8.1 that could also be part of the problem, the web is littered with reports of broken installations after the W8.1 update, I had to do clean installs of 8 on both my laptop and desktop after installing the 8.1 update.
That said, I'm also about ready to give up on Microsofts latest experiment. Some of the changes they've made are at best counter productive, most are just plain stupid.
Not sure about your combination, from what my reseller said, my combination of Lenovo/Win8 Pro can be "downgraded" by ringing Lenovo support, apparently they then supply a downgrade key and you can supposedly use any W8 distro. How that works in real life is another thing, I can imagine that tracking down appropriate driver downloads will be a chore.
I believe that pretty well all OEM W8 Pro installs have downgrade rights.