Did you make a new admin account for yourself to use when you got the system? If you did, all the previous user's photos would be gone.
Even if you have no user photos stored, there will be some photos shown in that storage number as it includes some graphic images that are part of the OS.
Hi , he had deleted his profile and I have a new one. I just thought 4Gb was a lot of images. I don't have an install disc or anything so was a bit wary of starting completely fresh.
If the old account was deleted and you have a new account with no photos, then yes... 4GB is a lot.
Open Finder and select your Pictures folder then hit command-i and tell me what it says for folder size?
Ok found the pictures folder by going through the hdd. It's only 1.5mb
Hmmm.... are you sure his old account is gone? Open Finder then go to Macintosh HD/Users and what do you see there?
What OS X version are you on?
I am on mavericks.
This makes it easy. Just command-r boot to the recovery screen then use Disk Utility to erase Macintosh HD to Mac OS Extended (Journaled) format. Then quit Disk Utility and click reinstall OS. The 5GB OS will download over the Internet and install. You can setup a new account at the end of the install.
Of course this will erase any data you have on there now.
Always reinstall an operating system from scratch when you buy a used computer.