Grand Theft Auto IV/Vlad

The following is not a walkthrough (which you can find all over the Web) so much as tips for completing difficult missions when all else fails.

Bull In A China Shop
There's no reason to have any trouble with this mission, assuming you go back up the block to where you are prompted to pick up a brick, then go back to the store, pull the Left Trigger ("LT") to bring up an aiming circle and use the Right joystick ("R") to aim at a window, then pull and release RT as prompted.

This is just a training mission for how to handle grenades.