60mm macro is good for full frame but 100mm macro is better for crop sensors...ie t2i,3i,4i.
Also you wont see much difference so long as they are all shot with a good amount of light which id assume they are. the t4i is substantially better in low light situations though.
I think might have that backwards. 60mm on crop would be the equivalent of 96mm on Full Frame. 100mm on crop would be 160mm equivalent.
I don't think a non-DSLR will do a fantastic job of Macro shots. Depending how close you want to get the 60mm or 100mm would both work. I'd go for the 100mm. You'll likely need a tripod as well.