There is no such thing.First of all, MSPaint can only save as .bmp (maybe .jgp too? dunno), which can't be transparent (neither of them).
Actually, Paint has always been able to save in various formats, just never has had the ability to save transparency even if the source image already had it.
Nope, try GIMP or Paint.net
That.
Paint.net is easier, get the forget out.
You mean you get the forget out and learn how to use Gimp,if you dont know how to use it than learn how to by Looking at something called a T U T O R I A L