Personally, in your case I would reformat. Who knows what kind of bug you may have. But first, I would get a copy of Spy-Bot Search and Destroy too(its free), run it, and pay attention to missing system files that maybe referenced in the registry as well as trojans and spyware. As Karma-Girl mentioned there are a lot of nasty worms out there on the net. I hope you have a good firewall too. It sounds to me that you installed something that contained spyware or you got a trojan that a good firewall would have blocked. And they will hog your system resources gathering information to transmit when you connect to the net. Running Spybot will tell you if you do. But, regardless, if you find adware or trojans or missing system files, I would reformat. You never know what damage has been done to your system. Sometimes when you uninstall software, it will erase system files that it updated. But, I've uninstalled object desktop many times and reinstalled it without problems.
As far as Object Desktop, did you uninstall all the free copies before installing the purchased version. You might get conflicts if you didn't.
Also, I would erase the directory as well, because files maybe left after an uninstall. I would also restart my computer after each install of Object Desktop Programs.
Lastly, I would be careful applying non-manufacturer drivers from Windows Update. They have a lot of third party drivers(MWD Drivers for soundblaster and NVidia) that once I installed my system crashed and I had to reformat my whole system. My system just wouldn't start right, like you. They just seemed to clog up my whole system. And of course, Microsoft accepts no responsibility for third party drivers. If you need drivers get them from the manufacturers website. Good Luck.