Originally Posted by Regalicious

Go to settings->Applications->USB settings and choose Mass Storage mode

Connect to your computer via USB

Drag down the notifications bar and hit Mount

Open My Computer

Open the phone

Create a folder called "Videos" (Or whatever you'd like)

Put movies/tv/video files in that folder

If you want to better organize, you can create as many different folders if you want ... files are organized by folder in Gallery so you can (for example) have a "Movies" and "TV" folder inside your "Videos" folder and when you browse the Gallery it'll have a separate stack for "Videos" (if any are directly in the Videos folder), "Movies," and "TV"

When you're done transferring, Eject/Safely Remove your phone on your computer then drag the notifications bar down and hit Unmount then unplug your USB.

You can also transfer to/from your computer via Bluetooth although it might take forever for giant video files.