It doesn't complete quickly (unless you have like no files). And Windows doesn't give you the status of it, except now, in Windows 10, you have that message.
The more files you put in the index, the more the search will suck and the more time it will take.
Are you searching for dll's files and system files on a regular basis? If so, sure include them. If not, like 99.99% of the population, and prefer to search for documents, files, and relevant thing you can run, then no. You should have only your Start Menu folder for your account, Start Menu folder for all accounts, your personal file directories. Outlook adds an entry for e-mails, if you have that, Windows also adds by default: IE history, and you have Offline files and Windows sticky notes. Up to you to keep them or not. If you dont' use them, then would be empty and you lose nothing.
Just remembered, I believe you can force the index to take place. In the search box, type: action, and select "View Recommended actions to keep Windows running smoothly". Then on the panel that opened, expand "maintenance", and click on "Start maintenance"
On the default repair thing, it would go through something like 5000 files and would say repair complete (or something to the liking) underneath the amount of files. I've got it running maintenance now though so I'll report back when it completes. Thanks for your help so far!