CAN YOU HAVE ONE SHEET WITH FRACTIONAL DIMENSIONS AND ANOTHER SHEET WITH DECIMAL

nope - document settings are for the document (hence the name).

you can change the units for any dimensions you want to be different than the document setting in the property tab for the selected dimension(s)

Dual dimensions is an option, but they fill up a drawing pretty fast..

You can place your dimensions then change one and use the format painter tool to change the rest (a little faster than each dim).

Dim Style is another option