IE won't fully launch 75% of the time

I just finished a long (3 months!) troubleshooting session to get malware off my PC, but there's one symptom still occuring: When I click on the tray icon to start Internet Explorer (Windows XP), about 3 out of 4 times, it doesn't completely launch. I get the hourglass but then it goes back to a pointer. When I check Task Manager, there is no application listed, but there's an iexplorer.exe (or in all caps) with about 12k-15k mem usage but no CPU usage. There's nothing else hogging CPU (System Idle proc stays high). I've taken to doing an End Process on these little orphans as soon as I create them, and I've also gotten superstitious: 1) I think they are may be the reason that sometimes if I have multiple IEs open, one will freeze after a while, and 2) lately it seems as if when I have Task Manager running & open on the screen, the orphans don't occur & IE actually launches completely (CPU registers, Mem Usage spikes, window becomes visible).

If I click a link, such as in an email, and a new IE window launches, there are no problems. There are, however, problems if I try to launch from the Start\Programs menu just as when I try to launch by clicking the icon on the desktop or tray.:confused

Any ideas?