Forgive me, however, there's a post/article you might be interested in reading. I have no idea what your technical capabilities are, however, it's a good read:
Fix a Lion file-opening hang in Mac OS X 10.7.2 | Macworld
Follow the instructions, and your ills may be addressed. Short version, and I can't get into it here, but during iOS beta testing I discovered a new profile in each of my iPhones during beta testing, and I worked through it with Apple Security - they deemed it was not a threat, and instructed me to delete the profile from each of my iPhones. My iPhones weren't working well during that beta, until I deleted the Profile and rebooted my iPhones. iCloud services were working much better after that...
The name of the suspect profile included the name "Ubiquity". Apple never fessed up as to how the profile was installed on my iPhones. I've removed the Ubiquity directory from my Mac a few times, and iCloud always works better afterward. YMMV.