do i have to buy new software to run goggle chrome?

i downloaded goggle chrome,on windows vista home primeum. it say that i should download quicktime7,but if i do it will automatically disabel the functuonallity of qucktime 6 pro users,how do i know if i am or was a quicktime 6 PROuser.i do not want to have to purchase the download i would need if so? please help if you can,thanks waaldo.