How to reinstall windows 7 after lubuntu 14.04

Hello everybody,
I wanted to make a dual boot on a Gateway lt4010u notebook which cane with a preinstalled win 7 starter. I hit a wrong command erasing windows. I have now lubuntu 14.04.
I want to get rid of it and install windows 7 or at least xp back. This machine doesn't have a dvd rom so i made a bootable usb.
I accessed the Bios and chosed already usb as first.
The thing is that it does't start the booting process, it enteres into lubuntu,.
I don't have much information on it so i dont mind erase everything.
I've installed gparted but for some reasen i can't upload the print screen ive made. But it's something like this:

Partition---------- File System ------- Mount point--------- Size------------------- Used------ Unused------ Flags
/dev/sda1 ------------- ext4 -------------------/ -------------------------267gb -------------11gb--------------------------- boot
unallocated------- unalocated ---------------------------------------29gb - - ----------------------------------------------------

/dev/sda2 ------------- extended ------------------------------- ---- 1011mb-----------------------------------------------------------
/dev/sda5 --------------- linux swap ------------------------------1011mb -----------------4kb ---------1011mb

I've read something on some forums but i'm not sure. I've made the unallocated partition but i got stuck for not knowing what to do for sure. I have little knowledge of this things.
Please, if somebody can tell me how to get back to windows erasing this lubuntu.
Thank you in advance!

Likely a bad installer. Start over with a fresh ISO for your licensed version using tool provided to burn to DVD or stick from Steps 1 and 2 of Clean Reinstall - Factory OEM Windows 7 then stick closely to those steps which will assure you get and keep a perfect install.

Thanks for the answer but i think it doesnt answer my question.
The problem is i cannot install windows beacause it doesnt enter into the boot process. It loads lubuntu directly everytime.
So i heard people talking that windows doesnt recognize file system ext4. And that i have to create a difrent partition. In this conditions what i can do to go through the whole process step by step? How can i start the boot process?

I explained why your installer is likely not booting. If changing it out from the link doesn't help then reset the BIOS to defaults and try again. Next try DVD.

Set HD to boot first in BIOS setup and trigger the boot device using one-time BIOS Boot menu key.

Do you have a UEFI BIOS? This requires booting the device as UEFI unless you want to Bypass UEFI to Install WIn7

The partition formatting has nothing to do with whether a device will boot which supercedes the HD and its contents. Once you get it booted by either of the above methods I'd wipe the HD with Diskpart Clean Command to create new partitions. You should always delete all partitions during an install anyway.