Backups?

[Grandpappy]

I did a full backup of my main drive(it showed 161Gb of the drive used) onto an external WD Passport drive of 250GB capacity , which took about 1hr.30m. and when I checked the external drive it showed only 43.5Gb's used. Is this sort of compression normal or has something gone wrong? I don't know of any way I can 'open-up' the saved file to see just what's in there. I used the basic method of backup using Windows7 .
Any ideas or explanation of what's happened or should I try using a commercial backup programme?
Cheers for any help.

[hc4361]

I suspect only your files have been backed up - photos, documents, music, videos, emails etc.

Are you using Windows 7?

[hc4361]

Yes, you are using Windows 7.

[hc4361]

You need to create a system image:
http://windows.microsoft.com/en-US/windows7/Back-up-your-programs-system-settings-and-files