Cant run 64-bit?

Hi! I have a pretty old Macbook pro, -08, but with Core2 2duo and running lastest version of OSX. Shouldnt i be able to run the 64-bit version? When i tried to install it it didnt show up, but when i install the 32-bit version it shows up. Im very intressted to have ANA run as smoothly as possible to be able to use/buy it.

the 64bit version is more picky about what CPUs it can run on… it wont run on some core2duo or xeons.

Ok, must be that then,thanks!