You said you want the (5A) breaker to blow before the (5A) fuse. It won't. Breakers will tolerate significantly higher amperage than their rating for awhile before blowing.
Another question: how much does the spotlight draw? Maybe more than 5A!
Options include, inter alia, putting a larger fuse or breaker near the battery on the line to feed the outlet, and putting just a switch at the outlet. Then, you'd want a fuse sized for the DVD/TV in the line or cigarette lighter plug to the TV.
I think I'd use a 15A fuse or breaker near the battery, use AWG12/2 marine wire to the outlet, and install a healthy-sized toggle switch at the outlet if you want to switch it. Then, just run the "constant on" wire to the hot side of the switch, not all the way back to the battery, with an appropriate (small) in-line safety fuse.