I have a psp w/ 2.60 fw on it. Can I run devhook or similar on it to run from mem stick or not - plz help.

You can run DevHook or similar in one of two ways, depending or not if you have a TA-082.
Use the image to see if you have a TA-082: http://www.maxconsole.net/content_img/ta82spot.jpg

Either way, the first step is to upgrade to 2.71 using the file here: http://www.psp-hacks.com/file/525
Put it in "ms:\PSP\GAME\UPDATE\" and run it from the Game menu of your XMB.
Then install Homebrew Enabler (Revision D) for 2.71 from here: http://dax.lan.st/

Now if you have a TA-082, then the only way to run DevHook is via the launcher for Homebrew Enabler.

If you don't have a TA-082, you can now use Update Flasher for 2.71 (also on http://dax.lan.st/) to downgrade to 1.50.
You need to use the the 1.50 EBOOT.PBP file here: http://www.psp-hacks.com/file/4
Once on 1.50, you can run all homebrew, including the latest DevHook.
You can also choose to upgrade to 2.71 SE-C (also on http://dax.lan.st/) which lets you run ISOs easily from the Game menu, or run DevHook from the menu.

Make sure that you do NOT try and use Update Flasher if you have a TA-082, or you will brick (permenantly break) your PSP.

Thx, that should get me started. Is it possible that you can brick a non ta-082 this way or not. I want to only have to do this once. Also will hen-d run .cso and .iso or do you need devhook?

It is possible to brick a non TA-082 by upgrading to 2.71, downgrading to 1.50 or upgrading to 2.71 SE, but it is highly unlikely; I've done all of that on around 10 PSPs without a single brick.

HEN-D cannot run ISO files by itself, but as you mentioned, it can via DevHook.
However, I would recommend that you downgrade to 1.50 (and then maybe upgrade to 2.71 SE-C) to get full (and easier) support for homebrew.

Well, I installed fw2.71, devhook .046 and henD and it all works perfect. Thx for all your help. I didn't downgrade to 1.50 because I figured if I could use 99% of software and not risk a brick that would be cool. I did download gta:lcs and it freezes at load screen, any ideas? Thx again.

is it a CSO? I heard that GTA freezes if it isnt ISO.

Is there a way to put .cso back to .iso format or do I need to find links again. Where I found this one, the .iso links are dead now

I can play the iso but not the cso for gta lcs but kind of lag because I put the speed as 222 not the 322.