New iMac iPhoto imported all my 35000+ system images

So after my Dell died for the 2nd time in a year I went and bought an iMac. I started iPhoto after I booted it up and it started importing all of the icons, image files etc from the system folder. Now I have all 35000+ pictures in my iPhoto albums.... I can not get them to delete and I am nervous if I do get them to delete they will be erased from the system screwing everything up... has anyone else had this issue? if so how did you resolve it?
I am noew to Mac's, well It has been about 18 years since I had a Mac.... Any assistance is appreciated.

Actually, you omitted the part where iPhoto asked if you wanted it to search your hard drive for images and you clicked "yes." It did exactly what you told it to do.

Unless you messed with the defaults in iPhoto, the library you now have is entirely composed of COPIES of those graphics and whatnot so you can safely delete the entire contents of the library and start over, this time using the "import" command from the File menu to import just the files you specify. Or you can just delete the images you don't want and leave the rest, your choice.

To be on the safe side, of course, you should have a backup before you do anything major.

That's the problem with computers ... they're a bit TOO literal sometimes ...