What is the differance between fondant and GumPaste. I am new to decorating and am not sure which one to use on my Mother in Laws retirement cake. It will have a sun flower theme?

gumpaste is similar to fondant, but without any of the softening ingredients like shortening or glycerin. gumpaste dries really hard, so its ideal for decorations that you don't intend anyone to eat. you can make the dec's far in advance then just add them to the cake. fondant is what you would want to use to ice your cake, because it will stay soft. you can also make dec's with a 50/50 gumpaste fondant mixture. make sense?

She is correct. You don't want to cover a cake in gum paste. It dries a lot faster than fondant and is used in much smaller quantities.
Rolled fondant is popular for its look but you might want to find one that you like and then work with it. A beautiful finish is what people use it for.
good luck
Claire