Problem with Migration Assistant

Have you enabled File Sharing on the iMac? Did you follow the MA instruction for transferring via Ethernet?

How to use Migration Assistant to transfer files from another Mac

Migration Assistant tips and tricks

iMac (27-in, Quad Core, Late 2009)- Migrating from OS X v10.5 Leopard with wireless migration

What version of OSX on the iMac?

Can you explain the Ethernet/Wifi thing, I'm a bit confused about what you're using.

There is only one File Sharing option to check. Not sure what other boxes you mean unless you are referring to other sharing options such as Printer Sharing. None of those are needed. MA provides a couple of import options such as from a Time Machine backup, Another Mac, an Attached hard drive, etc. You would not select the Time Machine option, so one of the remaining ones should work. Also, are you running the MA on the new computer or the old one? You need to use the former.

Full instructions are found in the link I posted earlier: How to use Migration Assistant to transfer files from another Mac. You need to scroll down to the part for using Wi-Fi or Ethernet.

If you’re already configured an account on the new iMac that uses that same user name as you’ve used previously on your MacBook you’ll see a red warning that reads This user needs attention before Migrating. When you click Continue a sheet appears that gives you the option to either replace that account with one that has the same name or keep both user accounts (in which case you must create a new name for the account you’re transferring over). Make the choice you want, click Continue, and the account will be restored.

http://www.macworld.com/article/2066996/how-to-transfer-backups-from-time-machin e-to-a-new-mac.html

Good to hear, I'd let it go, many times it's still calculating how much is left to do at the same time it's doing it, the Time Remaining isn't reliable, & often goes up as it's working.

I'd say if it hasn't changed at all in an hour or so to start over.

Did it finish yet?

I am now into 7 hours of stuck on 2 hours and 4 minutes to go.

Both are updated. Going from iMac to a new mac Mini.

Never sleep on both. Ethernet cable.

On this second try I deleted all users on the Mini so there would be no confusion.

Do I try for a third time?

Do I just stop and figure what hasn't been transferred and do it manually?

Well, here's my experience with Mac migration from an 8-year-old iMac to a new one. Slow, slow, slow and, in the end, unsuccessful. Be patient, forums like this advised, so I was, but after more than 48 hours, my data still hadn't finished transferring. So I shut it down, opened the new external storage device I'd bought with my new iMac and used Time Machine on the old iMac to save the data. (My previous time machine storage device had quit working). I'm now in the midst of transferring data and documents to my new iMac. I expect using Time Machine and the external storage device will be more successful than connecting the 2 computers by Ethernet. So far so good.