There are bunch of articles and softwares available online to achieve this. So instead of writing another tutorial, I am sharing the available tutorials which I have used often when I needed.
Here are the links:
Make your own bootable Windows 7 Flash Drive
- Recommended: http://kmwoley.com/blog/?p=345
- Without using any additional software: http://maketecheasier.com/boot-and-install-windows-7-from-usb-flash-drive/2009/01/23
- With Microsoft provided software: http://store.microsoft.com/help/iso-tool]http://store.microsoft.com/help/iso-tool (only 2.6 MB)
- Using 3rd party software: http://maketecheasier.com/updated-boot-and-install-windows-7-from-usb-flash-drive/2009/09/ (only 6.7 MB)
Make bootable Ubuntu using Flash Drive
Actually this is very much easy, and same for all distro. all are free n opensource.
I hope it helps, if you need any help, let me know.