I'm getting the same problem on two Windows Vista machines. It entirely locks my machines up and need to cold boot to get them back.
Only thing I've found that works sometimes is to open Reader prior to opening IE. So it seems that there is some incompatability occuring between the two.
I have the same problem on Vista Business.
When I open a document, acrobat freezes after about 5 seconds for 3-4 seconds. Then it works again.
This is independent of opening PDF-files directly or via the browser.
One workaround, I found, was to always have acrobat open, because it only happens, if acrobat is not running yet.
Hello. I had a similiar issue with Adobe 9.3.2 on my DELL Precision T3500 running XP Pro 32bit. When I opened a PDF it would freeze for about 10 seconds then come to life. Whilst it was frozen my PC beeped and I could not open any other program. After much troubleshooting I found the issue to be caused by the Nvidia NVS 295 Driver. I updated to version 184.108.40.20646 and this resolved the issue. Hope this helps.