Is this a Malware problem?

Noticed some problems recently (last 2 days) with the computer. Trying to open My Computer or in any way browse for files (in notepad, explore from Start Menu right-click, etc.) generates a "Windows explorer has encountered a problem & needs to close" error message. The day before I used Ccleaner on my registry (removed the usual missing file keys, etc. I have been uninstalling a lot recently.) and it also removed three lines I was unsure of but deleted anyway. If my memory serves, they went regsvr32 /u C:\...\???????.dll. These files, which are still in the application data folder, had filenames that seemed to be random strings of letters (Google couldn't find them). So my first question, what happens when you unregister a .dll, and should I have left it alone?
Since explorer has blown up, I was forced to run MGTools from the start menu by clicking on run and typing C:\MGTools\getlogs.bat. I used DOS edit from the command prompt to check over the logs and see if anything drastic has happened since I did a test run of the programs before using Ccleaner. Aside from my wife installing SweetIM, I don't see any major changes.
I had installed Kaspersky AV to get a 2nd opinion after Norton found nothing, and have since uninstalled KAV. I ran AVG antispy twice and after clicking apply all actions then reports, it tells me "No reports available". I triple checked the settings and they are exactly as set down in the sticky. AVG, incidentally, found nothing but some tracking cookies. I'm going to close Firefox and rerun AVG to try to get a report, but first I wanted to submit the other two since AVG found nothing anyway. Hopefully the answer is in the logs.
I have one final question, unrelated to my problem, that I have wanted to ask for a while (it's the reason I joined): How do you get to be a Malware expert? I have learned a ton about computers and malware following a bout with Zlob and a trojan last year, and I would like to learn more, and possibly help out if I can. Before the computer started acting up, I was planning on checking out some of the back logs and solutions that have been posted to get some experience, but now I get to ask for help. Sorry for the long message, but thanks for any help you can give.
Now to log off, close down and wrestle AVG for that report. Thanks again!

 

Got the AVG report. 4 tracking cookies in all their resplendent glory. Sorry about replying, but the scan takes 40 min, and the edit button didn't stick around that long.