Transferring data between old iMac and new iMac

Hi all.
I have a mid 2010 lowest spec 27" iMac which has USB 2.0. I have just purchased but not yet received the new 27" iMac. I have some large files on my old computer...about 150GB which is mainly a aircraft simulator called x-plane 10. I want to transfer all of these files to my new machine. A couple of questions:

1. Is USB cable my only/best option?
2. Approximately how long will it take to complete the transfer?

(note i do not have a separate DVD drive to hook up to my new machine)

Separately, given the specs of my old machine...how can I use it as a second monitor effectively (ie it does not have thunderbolt)? I have read some posts on this subject but could not make sense of how to set up. Note not using bootcamp or anything like that. Is there a particular cable or something I can buy?

Thanks in advance!!

Get a USB 3.0 external hard drive to backup your information.

1) Use CCC (Carbon Copy Cloner) or Time Machine to backup the information to the external HD from your old computer and set the format to extended journal case-sensitive (if you have a Fusion Drive).
2) After the backup you should use migration assistant to migrate your data, which will take approximately 30 minutes through a USB 3.0 HD or 1:30minutes+ if using a 2.0 device.

You can also use a ethernet cable to migrate your information between the two units if you don't own an external hard drive.

boto said:

Get a USB 3.0 external hard drive to backup your information.

1) Use CCC (Carbon Copy Cloner) or Time Machine to backup the information to the external HD from your old computer and set the format to extended journal case-sensitive (if you have a Fusion Drive).
2) After the backup you should use migration assistant to migrate your data, which will take approximately 30 minutes through a USB 3.0 HD or 1:30minutes+ if using a 2.0 device.

You can also use a ethernet cable to migrate your information between the two units if you don't own an external hard drive.

Click to expand...

Why does it have to be case-sensitive?

I may be even more confused now! I do not have an external hard drive (ie no backup to my current machine - probably not a good idea but anyway!).

My new iMac has the SSD only.

I thought I could boot both machines up and somehow drag and drop the key files?

I am not concerned about keeping my profile etc as don't mind setting up on the new machine.

Can you explain what the steps are when you say "You can also use a ethernet cable to migrate your information between the two units if you don't own an external hard drive. "?
Thanks!

ps: I am not very technical!

Weaselboy said:

Use Migration Assistant to move the date over. Once you start the new machine you will be asked to select a language and time zone, then start Migration Assistant. Once it starts, tell Migration Assistant you want to use ethernet to transfer. It will prompt you to start Migration Assistant on the old machine and connect a wired ethernet cable directly between the ethernet ports in the two machines. Then click start transfer and drink a beer or something while you wait.

You can read more info here.

Click to expand...

Just did this Wens, worked fine, took about an hour. All you need is an ethernet cable, take the one from your modem.