If I understand correctly your problem, the touch screen of your PDA is not working.
Well, this is a common IPAQ failure. When happens, the only options to repair it are:
1. Soft reset of the PDA. If still does not work, then go to next step.
2. Replace the top digitizer glass.
It requires a very skillful person to do it. If you have not experience with fixing electronic devices, then I do suggest you to send it to repair.
Besides that is necessary to open it, you will require a soldering iron, and desolder the digitizer part and remove it from the LCD screen, which if is not done properly with the right tools, it's easy to damage the LCD screen assembly.
Also, if it's not opened right, is possible to damage permanently the mainboard if is bent or warped.
Also, even though there are a lot of cheap digitizer replacement parts on-line (mainly from China), they have a compatibility issue that prevents to use them in the RX3715 (or RX3115) PDAs.
I have nothing against Chinese manufactured parts, but after buy around 10 digitizers in the last couple of years for different Ipaq PDAs, I found out that only 3 worked fine, so I know what I am talking about.