Transmission Fluid replacement

I have a 2005 Hyunday Sante Fe with about 34600 miles on it. My dad noticed a leak under my car and told me it was transmission fluid. I went to my dealer (where I had just had an oil change on 10-3-07) and told them I had a leak. They checked and told me that they found a leak at the O ring on the oil filter and that my transmission fluid was really quite filthy and should probably be changed. They also added a quart of oil because I was low…to which I replied I just had the oil changed a little over a month ago, was I also leaking oil and they told me maybe and I should watch it. The bill included 4 – ATF-SP III and 3 — 80W90. Aren’t both of these transmission fluid…one synethetic and one regular…and why would I need both?