First, please make sure your backup HDD is formatted to NTFS. Then, make a folder for W7-images.
Start Macrium, locate your OS disk (usually the first one), make sure all partitions are selected, and click Image this disk.
Point the image to the new folder you have made in your backup drive, for W7 images.
Then, click on Advanced Options:
Compression = Medium (Recommended)
File Size = Automatic
Password = (enter only if you want to password-protect the image)
Auto Verify Image = check the box so it will verify after creation
Comments = put some specific notes in here so you can identify this particular backup, should you need to find it exactly in a batch of backups.
Shutdown = gives the option to shut down the computer or hibernate after completing (handy if you set this up to run at night in the future).
Uncheck Full and Differential, as we're only making one image right now.
No schedule on this one - it's a one-off.
Uncheck Save backup and schedules as an XML....you won't have to give it a name then.
Click OK. The image will run, and give you an estimated amount of time it will take. The verification will take just about as long. So if it says 30 minutes for the backup, you can guess it will be about another 30 minutes for the verification.
When it's complete, please post the screenshot for us to see.
Then, go back to the main screen, to make your rescue media.
Macrium will create the rescue media based on the installed OS, so this will be your W7 rescue media.
Click Next and Next again. If Macrium tells you there's an update, please take it.
Select how to create the media: CD/DVD, ISO or Flash drive.
The multiboot option should not be available for your W7 system, I think.
Create your rescue media. Then, be sure to boot your system to it, to make sure it's good. Should you need to restore an image, you boot to the Macrium rescue media, navigate to the image and restore your system.
Once this is done, you can go ahead and make all the updates/changes to the system, verify everything's working correctly, then make another image for posterity.
Hope that's clear. Please ask if any questions.