How do I fix my psp when it says to use this content you must activate the system?

LOL, looking at all of these answers.
a few points to make:
1)yes, you do need a pandora battery and a magic memory stick, here is a tutorial on how to make both, suggestion: buy a pandora battery instead of making one, some sites have it cheap.
Dont be afraid of bricking(breaking) your psp. You can downgrade it using a pandora battery and magic memorystick again if you do. HOWEVER, this does not mean you dont have to be careful, be cautious and follow directions carefully.DVD to Apple TV Converter for Mac, top Mac DVD to Apple TV converter, can rip DVD to Apple TV video MP4 and transfer DVD to Apple TV on Mac easily.
once you have a pandora battery and magic memorystick, you're all set to go to downgrade it and then you can just place your games into an ISO folder on your memorystick. here is a tutorial on how to do thatMac DVD to iPhone software is the best iPhone movie converter for Mac which is able to convert iPhone video on Mac OS X.
Find someone that can hack your psp and install custom firmware. Some stores do that for a small fee. Don't try to install custom firmware yourself because any mistake you do can PERMANENTLY break your psp.
Download some iso or cso game files from the internet or buy them from stores. You can find the games you want using www.torrentz.com search engine or from psp homebrew sites.
After you've got the custom firmware and some games, put them on your PSP's GAME folder. You need a mini USB b-type cable which is very very common and you probably already have it.
Buy them at the store, and put the disc into your PSP. Asking how to steal games is against Yahoo's community guidelines.Video Converter for Mac is a professional Mac Video Converter which can perfectly convert video on Macintosh.
I've just got a PSP 3000 which I bought three days ago.I've never had a PSP nor have I played any games on it.I have the PSP but i don't know which games would be the most fun.I need help finding games that are worth buying at this time.My interest is mostly action FPS or sports genres.
Well, theres always the faithful Grand theft auto, both vice city stories and liberty city stories. For sports i reccomend
If you would like to try out a pair of great rpg games, i reccomend God of war chains of olympus and Final Fantasy Crisis Core.
Good luck, and have fun