Which of the following scanners have better optical resolution:
Epson Perfection V700 PHOTO, Epson Perfection 4990 PRO, or Epson
Perfection V750-M PRO

Also can they scan paper money?

Some of the color copiers  recent makes do not allow color copying of money
 bills

Can they scan paper money?!?! Why sure, your scanner will scan
anything, it doesn't know you're committing a crime:

Crime and Punishment
http://money.howstuffworks.com/counterfeit8.htm
..."Under federal statute 18 USC section 471, if you're found guilty
of making copies "in the likeness and similitude of US currency ...
unless they are much larger or much smaller than US currency" (a
minimum of 50 percent larger or 25 percent smaller) or unless they are
"rendered in black and white," you face up to 15 years in the
slammer..."

...and THAT's just for making it. Try spending it, the years in a
federal penitentiary really multiply then.

I really think you should reconsider.

Holy Cow, read these:

HP Helps U.S. Clamp Down on Counterfeiting (about printers)
http://www.hpl.hp.com/news/2003/july_sept/counterfeit.html?jumpid=reg_R1002_USEN

Fun with Photoshop: Currency Detection
http://creativebits.org/photoshop/the_money-shot_0
See the image...

I stand corrected.

you musnt do that cause you will be easily jailed as there are some
clues on every  print you have.The model or type doesnot matter.Every
printer signs a special mark  so that they can understand the source
easily.Also in those machines as coppiers in the Universities colleges
libaries and maybe in your printer or scaner mostly there is a special
program and some deviceses to record what you scane print etc...
 Big brother is real, this is known since 1970's so think about 2006...