Zeppelin
If you want your laptop to run youtube to watch sponge bob, it is possible. Not only that, it is easy and inexpensive.
You can run Linux from a bootable USB flash drive. That flash drive will act as a HDD from which you can boot an OS. You will need to set boot priority in bios to boot from usb. If you have a spare USB of 2GB capacity, that will do for this purpose.
Linux is an OS just like windows. Linux is free and open-source. And it will let you watch Youtube on Firefox browser without a problem. Linux comes in many
flavors - such as Ubuntu and Linux Mint.
Linux Mint is said to be easier to use and similar to windows.
There are many tools available that help you create a bootable USB running Linux such as
LinuxLive USB Creator,
RMPrepUSB.