Windows XP Pro Revo-Uninstaller's 30-day trial issues

Yes, I built my PC. Unfortunately and am am “still” running Windows XP Pro. SP3.
My processor is an AMD Duron(tm) processor,MMX, 3DNow, 1.2GHz.
My system has 2.3Gig of memory, and my DirectX version is 9.0c (4.09.000.0904)

Last week . . . after running quite well, Normal mode became quite sluggish and the mouse pointer generally freezing after five or ten seconds. ProcessExplorer would always be in the “red”, thus the machine would do nothing. I was constantly re-booting.

Each time I would attempt to run Malwarebytes I was told there was an Application error. Thus I removed Malwarebytes and re-installed it. Immediately after installing the program I would receive the same Error Message:: Application Error 0x00001d.

Also, I could not install Adobe Flash Player. After each “fresh” download a message popped up informing me that Adobe Flash Player had to close.

Researching this issue on YouTube, I ran across your website: http://www.cleartechinfo.com. In this video the narrator said to first download Revo-Uninstaller (which I did), and CCleaner (which I already had installed).
I could not locate the download button for the “Free” version , but I did see the 30-Trail of Revo-Uninstaller button and clicked to download the trial. When I double-clicked on the Revo-Uninstaller icon to install the program, the very first page that popped up asked for my Username and my Activation Key. Since this was a 30-day Trial I was a bit curious why are they would be asking for a Username and Activation Key when I will only using the software to assess its actual benefits.

I have some other issues but will send another thread for these.