can you write your enquiries in english?
gta iv is a poorly coded pc version of a console game. it heavily taxes a pc's cpu, ram and gpu. a pentium dual core with mobile nvidia gt gfx might not be up to the task.
http://www.tomshardware.com/forum/113964-13-requirements-info
http://www.tomshardware.com/reviews/balanced-gaming-pc,2477-11.html
http://www.tomshardware.com/reviews/balanced-gaming-pc-overclock,2699-11.html
have you downloaded patches released by rockstar?
search toms forums and gtaforums for more info.