Changing the default installation path

Hello,

I have a small problem here which I can’t seem to find a solution to. I have multiple partitions for Windows, Programs and data. I want to have all the programs on the D partition. However when I install a program it usually automatically sets the installation path to “C:\Program Files\”

I can off course manually change this directory by simply typing the right one but I was wondering if there was a way to make this default install directoy “D:\”

Also as a second question as I can’t seem to find anything helpfull on this matter either: is it wise to have all your programs on a different partition, is there a performance increase?