I am having the exact same problem as harlock15: 32-bit applications hang ("Not responding," but task manager shows that ample system resources are free) for about 75 seconds before a file|open or file|save as dialog box comes up. Furthermore, when the dialog box finally opens, it is "crippled" and I cannot fully navigate within it -- see the attached image. File|* dialog boxes within 64-bit applications still work fine.
I have tried CHKDSK and it returned no errors, but I cannot successfully run sfc /scannow -- it gets to "Verification 77% complete", and then returns the seemingly common "Windows Resource Protection could not perform the requested operation." It doesn't get any further if I boot into safe mode with command prompt, and the CBS.log file does not contain any obvious errors -- ieach scan just ends at the line, e.g:
2012-07-25 14:55:58, Info CSI 0000023c [SR] Beginning Verify and Repair transaction
Any thoughts about workarounds to reduce the amount of "not responding" time? Or is there some way to customize the file dialog box global settings specifically for 32-bit applications that might break me out of this rut?