'paste unformatted text' and spell check functions really slow

Over the last few weeks, the 'paste unformatted text' and spell check
functions in Office 2007 have become intolerably slow - taking more than 45+
seconds to complete the task that used to be instant.

The problem occurs every time I try to use these functions and it common
across the entire Office suite.

I've tried completely uninstalling/ reinstalling Office, removing all
registry entries, and deleting any residual folders, but it doesn't make any
difference.

The only tangible changes to the laptop have been installing Windows 7
Professional RTM and the update to Office Service Pack 2