My 2003 Jeep Grand Cherokee has a blower problem. The vent/AC blows out of the floor and Defroster when I accelerate, when it is supposed to blow out the front. Please let me know what you think. I think it is a vacuum hose problem

I think you are completely right. When you accelerate, you are opening the throttle up a little, or adding more fuel, either way, this causes a drop in pressure, which will cause the spring to pull the vent back into defroster mode. My friend has been dealing with this for years, and we still are not really sure what to do about it. What may be the cause, though, is if one of the vacuum hoses leak, it causes the lower pressure to lower still further, so check to make sure none leak.