1. Better insulation/sound deadening (just look at the lining under your deck lid).
2. ABS is standard
3. Duratec is an option
4. CD player is standard
5. Leather seating option
6. Fold-down rear seats
7. Power adjustable driver's seat (standard even on cloth)
8. Traction Control Option
9. Power heated mirrors (standard IIRC)
10. Power adjustable pedals option
11. Floor shifter option
Briefly, the differences between the SE, SES, and SEL vary over the '00-04 Tauruses...For example, the SEL from '01 and the SEL from '03 can have a lot different between the two...
The SE is the high volume Taurus that comes with the standard fare, power windows/locks/mirrors, Vulcan V6, aluminum wheels, six passenger seating.
The SES is a step up and comes with the power driver's seat, keyless entry, and has available as options the Duratec V6, moonroof, power driver's seat, floor shift w/center console, Mach Audio system, leather seating, electrochromic rear view compass mirror, traction control...
The SEL is the top of the line and comes with all the options that the SES had, plus machined aluminum wheels, heated mirrors...
Pretty much all SE models have nearly identical equipment, and all SEL models have nearly identical equipment. The SES models are the most mixed up with some having tons of options and others being equipped with so few it might as well be an SE.
Leave it to Ford to make this so complicated...For '05, the model lineup was simplified as Ford looks to send the last of the Bulls out to the slaughterhouse...