You'll have to contact the bank that holds the CDs, of course. They will need a copy of your grandmother's death certificate. Under the laws of most states, the CDs became your property by operation of law upon your grandmother's death.
The death certificate, coupled with confirming identification from you, plus your social security number, should be all that the bank needs in order to update its records to reflect your sole ownership, and ensure that any interest reporting for 2007 is done under your social security number and address.
You and your uncle may also be able to simply allocate the interest earned in 2006 between your grandmother and yourself when your uncle files her final tax return for that year. Check with your tax advisors on how to do that.
Finally, it's possible that the bank will waive early withdrawal penalties on the CDs if you need to withdraw the funds early. Many banks make that accommodation when an owner of a CD dies. You may have already found that your bank doesn't waive the penalty. If you have not, check it out just to find out what your options are.