I'm a mechanical guy and I don't know too much about electrical circuits, thus I ask for your help.  

I am trying to make a system that does the following:

On/Off switch is pressed and the system is activated.

3-5 hours pass (emphasis on hours) at which point 2 LED light's are blinked on for 1-2 seconds, every 5 minutes until the On/Off switch is turned off.

I was also hoping to intergrate a sort of interupt switch into the system, where if at some point during the intervaled LED flashing, there can be a switch pressed where the LED flashing is subsided for about 30 minutes to an hour, and begins again.

Anybody have any clues on how to do this?  I was thinking maybe a 555 timer, but I am thinking 5 hours may be too long.

Let me know what you guys think.  I appreciate it.