Mouse selects all text in any writer program

I can only use my microsoft word, notepad or notetab program for about 10 minutes at a time. After that, all text in highlighted. The only way to get rid of it is to reboot. I am using Word 2003, whatever notepad came with my Windows 7 (64 bit) and Notetab Pro 6.2. Frustrating trying to keep messages and writings down to 10 minutes or so. Thanks for any suggestions. I have tried disconnecting mouse and keyboard (both are wired to usb 2.0). Keyboard is microsoft 2000, mouse is logitech G300

I deleted Notetab 6.2 and I use revo uninstaller all the time. It did not do the trick. Microsoft word and notepad still have same problem. After 10 minutes or so, moving cursor results in all text being selected. I have 64bit Windows 7. My Word 2003 is most likely 32 bit. Would that make a difference? The Notepad came with computer, so it should be 64 bit. In order to getting a longer time using both, I found that If I use Word for 9 minutes, copy text to notepad and use for 9 minutes, then repeat back to Word, I can extend writing for up to 20 minutes. But what a pain.