I currently have IE 8 and Microsoft Office Professional 2007 installed (I had this problem with 2003 Word as well). I can't open up links in emails because Outlook freezes and if an IE 8 window opens, it hangs. If I try to open IE 8 normally, it hangs. I can open it up about 2 out 5 attempts.
I have run a system file check, and all files appear to be intact. I haven't run CCleaner for about a week.
I have been having this problem for about a month, maybe longer. I only installed Office 2007 a week ago and still had the problem for 2003.