OK - so here is what we are going to do, and none of this will cause you to lose your e-mails or contacts.
However, just to be on the safe side, I want you to back up your contacts, just in case something funky happens.
Please go to File > Open > Import.
Select "Export to a file" and click Next
Select Outlook data file (.pst) and click Next
Click Contacts and click Next
Then click Finish.
Now, if you wish, you can do the same procedure with an e-mail folder. You can simply select the top level of the e-mail account to back up everything under it (just make sure 'Include subfolders is checked') - However, this may be time-consuming, and I really don't think it is necessary at all to do, but if you want to feel extra-safe, you can certainly do it.
Now, once you've done that, it's time to close all Office programs (Word, Excel, Outlook, etc.) and do an Office 2007 Removal with a special program from MS that will only remove 2007 and not affect your 2010 installation. Here's the link to download it:http://go.microsoft.com/?linkid=9669698
Once you run that, Office 2007 will be completely removed from your PC.
Please Reply with additional questions as I am here to help you; otherwise, please click Accept - thank you.