If you want to install window 7 with the pendirve,
Firstly make the bootable pendrive.
Follow the below instructions:-
1. Insert your USB (4GB+ preferable) stick to the system and backup all the data from the USB as we are going to format the USB to make it as bootable.
2. Open elevated Command Prompt. To do this, type in CMD in Start menu search field and hit Ctrl + Shift + Enter. Alternatively, navigate to Start > All programs >Accessories > right click on Command Prompt and select run as administrator.
3. When the Command Prompt opens, enter the following command:
DISKPART and hit enter.
LIST DISK and hit enter.
Once you enter the LIST DISK command, it will show the disk number of your USB drive. In the below image my USB drive disk no is Disk 1.
4. In this step you need to enter all the below commands one by one and hit enter. As these commands are self explanatory, you can easily guess what these commands do.
SELECT DISK 1 (Replace DISK 1 with your disk number)
CLEAN
CREATE PARTITION PRIMARY
SELECT PARTITION 1
ACTIVE
FORMAT FS=NTFS
(or FORMAT FS=FAT32 some where use this command.)
(Format process may take few seconds)
ASSIGN
EXIT
Don’t close the command prompt as we need to execute one more command at the next step. Just minimize it.
5. Insert your Windows DVD in the optical drive and note down the drive letter of the optical drive and USB media. Here I use “D” as my optical (DVD) drive letter and “H” as my USB drive letter.
6. Go back to command prompt and execute the following commands:
D:CD BOOT and hit enter. Where “D” is your DVD drive letter.
CD BOOT and hit enter to see the below message.
D:\boot\bootsect.exe /nt60 h:
(Where “H” is your USB drive letter)
7. Copy Windows DVD contents to USB.
You can use the XCOPY cmd for the copy content form cd to pendrive.
You are done with your bootable USB. You can now use this bootable USB as bootable DVD on any computer that comes with USB boot feature (most of the current motherboards support this feature).
Thanks
Gautam's World 