Subtitle Workshop is the most complete, efficient and convenient freeware subtitle editing tool.
It supports all the subtitle formats you need and has all the features you would want from a subtitle editing program.
Subtitle Workshop makes subtitle creating/editing/converting tasks almost a pleasure, the amicable and intuitive interface mixes easy to access menus & must have features with advanced functions and a remarkable speed and stability, drastically reducing subtitle editing time.
It includes spell check function and an advanced video preview feature which will ease the task even more.
The best choice for the beginner, expert or the fansubber. Have a try, and you'll forget the rest!