iMac computer doesn't work

hi im concerned and don't know what is going on with my iMac computer when i turn it on it just stays on the start up screen with the apple icon and and icon that i spinning i have tried to reset it unplug the power outlet somewhere else unplug it from the back have purchased a new mouse and keyboard and nothing seems to work please help i have important pictures i want to recover of my father that passed away two years ago please help me thank you

iMac27/3.06/2X2GB/1TB/4670-256MB PartNumber:MB952LL/A

SerialNumber:QP******5PE

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