What are the commands in REPAIR YOUR SYSTEM option in windows booting disc?

I have a problem on installing the windows 7 to my dell inspiron 1545, while i am trying to install the os it shows that the partitions were allocated as DYNAMIC allocation, i need to change it to BASIC from the windows installation disc from boot up.. note that now i dont have any os installed.. my previous os installed did something wrong with my hard disk partitions.. please help me someone...