How do I put videos on a psp from the computer using a memory stick adapter?

As you have mentioned you got it in feb so it cant be 3gs for sure cause 3gs is launched on 19th of this month.the first gen doesnt have 3g speed for surfing the web. 3g is the faster way to browse the web. also the 3g is thinner.
First you need to register your device. you rgister it from the ps3 settings menu. then go on to the ps store on your ps3. download demos from psp section. instal them the copy them to your device.

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I am trying to decide between the Nintendo DSi and the PSP 3000, I want to know the different GOOD games for these systems. I am leaning towards the DSi because I know I enjoy the games nintendo releases. I want to know games that are coming out soon, and already exsist that are really good games.
psp has better games u can watch movies buy ps1 games on psn. the best games for it is FF7 crisis core, loco roco. u can rent movies for only 3 dollars on psn. i heard the dsi has many glitches and ive never ben a fan of ds games

Use a free Blu-ray Ripper software to ripping Blu-ray disc to PC, and then backup.

Personally i'd go for the PSP. The PSP is a better built console and doesn't rely on novelties.
The PSP's lineup is also ALOT stronger, for example, already out on the PSP you have;
Final Fantasy Crisis Core (Get this, awesome game!!!),
Final Fantasy 1 & 2,
Monster Hunter,
Killzone Liberation,
Silent Hill Origins,
Vice City Stories,
Liberty City Stories,
Wipeout Pulse,

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star ocean,
Final Fantasy 7 (download from PSN for just ￡7.99)
metal gear solid,
resistance retribution,
locoroco,
lumines,
god of war,
both tomb raider games
And if that's not enough good games, look at the release list coming out soon;
Gran Turismo,
Final Fantasy Dissidia,
Little Big Planet,
motorstorm,
collin mcrae dirt 2,
GTA chinatown wars,
Jak & Daxter: The Lost Frontier,
F1 2009
metal gear solid peace walker,
tekken 6,
resident evil portable.