Depends on if you have a 64 or 32 bit version of Windows...I did the 64 bit version..
There is a little more to it than that. Most folks who have relatively new pc's have 64 bit if they are running Vista, W-7, or W-8.
However most of the internet browsing is done on the 32 bit browser. A lot of web sites are not compatible with 64 bit and it really isn't needed for internet use anyway. If you use IE and are clicking on the light blue e with the yellow circle around it you are using the 32 bit browser. The 64 bit looks like a globe from outer space.
Most software is still 32 bit and installs in a folder called Program Files (x86) if you look at your operating system.
The 64 bit system is mainly for software that needs more RAM than is available in 32 bit, such as Photoshop when you have many layers on an image.
So if you use a 32 bit browser on your 64bit pc you need to download the 32 bit java. They explain that on their site.
I have multiple computers, like Triple R, and most folks today. Since I have to use a Satellite which has a daily download limit I am always looking for ways to save on that as well as save time.
As Bird said earlier, the normal java download is 128 MB. That is because it usually has some other program, like Google tool bar, or some other, which you don't need or already have.
If you go to their download that is called "offline" it is only 32 MB since it doesn't contain any extra stuff that you would probably untick before installing the 128 MB download.
You can put the download on a thumbdrive and install it on however many computers you have as long as they are all Windows or all MAC. You can download MAC and other operating system versions from the same page.
Hope this helps.
Ron