ok am confused now , first i thought devhook is the program that gives you the features of newer firmwares on a 1.50 , now i read that its used to run iso's

can someone please explain this to me?

i currently have version 1.50 , and all i want is to get the features of 2.71 , so which one should i download?

People with .5 install devhook two do two things... emulate 2.71 have the Internet browser ect. And to run ISO's an Cso's.
For example when you go to the devhook icon in the game menu and then memory card,- confirm to load that, then you get a list of options. They include what speed to run at, what ISo/cso to load or you can just load your UMD that requires a higher firmware that requires 1.5.
After you select start one of two things could happen 2.71 firmware is loaded along with an ISO,- and when you go to the ISO icon its your ISO not the game you have in the drive. Or it could automatically load your UMD or ISO. If the last option happens all you have to do it press home and you are loaded in 2.71 with everything 2.71 can run.
If you can find it then i would, if i were you get devhook 0.46 and furthermore the full install package. Just run the .EXE and plugin your psp and it will install devhook for you.

thanks alot , also its great that theres an installer , any idea where to get it from?
also if i do use that installer , will i have to do a certain thing each time i turn on my psp to get the 2.71 features or will they stay there for good along with the 1.50 features?

thanks again

no you can get a cuxtom firmware which you can have a "dual boot" sort of thing like the modchip but instead of having another nand flash your other flash will be actually on the memory stick its self and you can find FULL PACKEGES here at this site
also with the custom firmware you can also go into recovery mode incase you delete the index.dat or insert a bad gameboot, background, or font!!! i personally have herleg's custom firmware patch v.2 since the WLAN switch can be off and ill boot into my last emulated firmware
BUT THE CUSTOM FIRMWARE INSTALLATION WRITES TO THE PSP'S FLASH AND HAS A RISK OF BRICKING!!!!!!

after i have devhook installed , which option switched to the "dual boot" , and is it possible to make it go to that dual boot each time i turn on my psp so i dont have to do it manually each time i turn it on?
also when am in the dual boot , will i still be able to run the same and all of the homebrew i used to run on 1.50 including my custom theme?

hi, I instaled device hook v0.46 and I coud open it once to make all the settings but nog I can get it open
it says that the aplication is dammaged, is that normal of what should I do?

(I am dutch thats way my english isent that good sorry

You're most likely still in the emulated firmware, just press Home+Start.