I am looking for a decent 2500 under $10K for my daughter to use to haul her 2 horse trailer and usually only 1 horse to shows etc. I have found one for $10K with 48000miles, which fits in my budget...and sounds decent...but with 2WD.....I am getting conflicting info on whether this will be suitable or not. vs a 4WD..please someone that KNOWS reply! I want her to be safe and able to handle most hauling situations with this truck.

I do not see why 2wd vs. 4wd would effect your decision as far as being a tow vehicle. These trucks are not supposed to be left in 4wd anyway - it is not AWD. When pulling a big trailer I have never had a problem getting traction when taking off - it is that stopping part that poses a problem. I personally have 4wd because of the snow that we get in my area - it is more of a pain than a help though - you carry around a couple hundred extra pounds all the time and there is a lot more friction in the drivetrain and that equals worse gas mileage and a lot more stuff to break. But hey - if you wanted gas mileage you wouldnt be getting a truck. At our shop we have a 2500HD with the allison tranny, and we put thousands of pounds of aluminum castings in the bed and haul them all over the place - we have never had an issue with it. I don't know if any of that helps but personally I would be more concerned about the brakes than how many powered wheels there are as far as safety.

I have a 1998 2500 that I pull a 31 foot travel trailer without a problem... I have also pulled a two horse trailer with a 1500 and a 305. It is really all a matter of distance and frequency of the pull. The 2500 should give you great performance.

I pull an 18' dump bed trailer full of sand with my truck not using 4x4. There is so much weight on the rear axle that traction isn't a problem with rwd. Sometimes for a REALLY big load, 4x4 low is nice to have for the extra power. If your daughter would ever need to pull anything bigger, you can get a low range transfer case that just bolts right up to the transmission. The most important thing for trailering is power brakes, whether they are electric, vehicle hydraulic, or trailer tongue hydraulic. Any truck can get a trailer moving, but stopping can be another story.