automatic number strings like "44444444444444444444444" (what I call "ghost number writing")
i have had some mysterious writing like that, and the pointer was moving over the screen.....but it was solved when i put in new batterys in the wireless keyboard/mouse

upload suspicious file(s) to www.virustotal.com and test with 44 malware scanners
when you have the result, copy the url in the address bar and post it here for us to see

alternative
Jotti http://virusscan.jotti.org/en
VirSCAN http://virscan.org/

Then run a quick scan with this…

Malwarebytes Anti-Malware 1.51. http://filehippo.com/download_malwarebytes_anti_malware/
always make sure the program is updated before you scan
click on the remove selected button to quarantine anything found

post the scan log here