i've had exactly the two things you describe in your first post many times. I often use sandisk flash drives and they all have that piece of software pre-installed on them, i just delete it. if i want to put something encrypted on a usb drive i would use 7z to put the file in an encrypted archive then copy the archive to the usb. deleting the exe file will do no harm at all, the rest of the stuff in the folder can also go, the pdf is instructions for the exe file and if memory serves me there is a .txt troubleshooting or license file in their also. that software on the sandisk usb is not malicious but isn't very useful really. i have also had the "issue" of it calling itself a hard drive not a removable disc, but it still has options for safe ejection and it still works fine. this has happened to me on an xp computer as well as windows 8.
as for newburydave's recent post such evil devices do exist but it is unlikely that a genuine sandisk usb would be infected like that. make sure to get it in a reputable highstreet shop and that you see the packet isn't opened and you should be fine. the software on the sandisk won't help protect your pc from other malicious USB devices, it will only encrypt the data you put on the usb, your only solution to protect from such attacks is to ensure plug and play is turned off, even then it is not a perfect solution as recent developments show some devices can attack your machine without needing plug and play or any kind of exe file, this was in the news recently discussing edited firmware amongst other flaws in the usb format. the software on the sandiscs will be safe (as long as they are genuine one's from a reputable shop and you saw the packet hadn't been opened before you bought them) but won't help with protect against attack, if you want to encrypt stuff on a usb drive , a good idea if you have to carry confidential files around, 7z is probably better as i believe it will have a stringer encryption type than the sandisk software. as for securing online accounts i suggest not a random password generator but another type of "1 time pad", 2 step verification, having a password in your head AND a text sent to your phone really improves account security.
Back on this site, for a while anyway, been so busy the last year.
My systems:2 laptops, intel i3 processors, windows 8.1 installed on the hard-drive and linux mint 17.3 MATE installed to USB