Root Rooting problem with 2.2

[reventon]

I have stock Froyo done from ATT for captivate.

I tried to root my phone through superuserclick. But in the window it doesn't an option for root. In samsung captivate tab it only shows unlock code. For universal, it shows root and unroot and other options.

I also tried z4root, in that when trying to install through astro manager, i get the following error

Install blocked
'For security, your phone is set to block installation of apps not obtained from android market'.

Please advice what to do.

 

[SuFuCru]

Use the root button for universal and reboot your phone when it's finished.