Yes, ofcourse it will work with any file format. If you want to split a large ISO image (DVD)
format, then calculate how many lines it contains. Suppose there are N number of
lines and you want to split the file into 3 files (ie., N/3). Then you have to specify the
value of N in the options. For eg.,
split --lines=6000
There are very good file splitting & joining software available for Windows.
Try 'File Splitter Deluxe' for splitting & joining large files.
Get it from here:
http://www.softdd.com/filesplt/index.htm
You better use the above software. If you use Linux tools, then you must be thorough with it.
It's not recomended for beginners to use these command-line tools.