The Form 1099-R absolutely should NOT have code G. The Form 1099-R for a distribution from an IRA paid to you will have code 1 or code 7 depending on your age and the IRA/SEP/SIMPLE box will be marked.
After entering the Form 1099-R, make sure in the follow-up that you indicate that you moved the money to another retirement account (or returned it to the same account) and indicate the amount rolled over. TurboTax will include on Form 1040 line 4a the full amount distributed but will exclude the amount rolled over from the amount on line 4b. TurboTax will also include the word ROLLOVER next to the line.
