That is possibly the longest HijackThis log I have ever seen. A couple of things raised my eyebrow, but without knowing for sure I won't say anything.
First off, by entering the words 'online scan' on google will get you to some online virus checkers (which are good to run from time to time anyways).
Second, the upper and lower case of Explore.EXE makes me think something has altered it. Replacing it with a fresh one could be a good call.
Off the top of my head I don't remember if this is good for all files or just hidden, but try this. From the Start button open up Run and enter cmd. This will open the DOS box and enter SFC /SCANNOW. No need for upper case I did that to be clear on what is entered. SFC is system file checker and by itself will say "ok, but at next boot we'll do that". So the scannow, well I bet you can guess what that does. There is a space between C and /.