Which Hard Drive to install on?


I'm am running Windows Vista (lucky me!) on an Acer Aspire laptop. It has two hard drives, one of which is the C: drive and is named ACER (66.8GB free of 110GB) and the other, D: is named DATA (74.4GB free of 110GB).

I don't really know much about partitioning and would appreciate any advice on which is the best way to proceed in order to have the option to dual boot in the future.

Much Obliged, Thanks.