Thanks for the encouragement, mat. I also wonder if it will screw things up to have the primary OS windows 7 64-bit and the old drive is 32-bit.
When you set up new SSD to be your main drive and old HDD to be secondary drive, you got 2 options:
1. Install fresh new OS windows 7 64 bit onto your new SSD and save the old files in your old HDD to a back up device and format it
2. Migrate your data from your old HDD to the new SSD and then format the old HDD to be used as secondary storage.
Option 1 is easiest and fastest.
Option 2 you have to retain whatever OS from your old HDD and you can't change anything. So if you have a 32 bit OS on your old HDD, the new OS after migrating into the new SSD will also be 32 bit. The other problem with this is that SSD requires a bios SATA config to be set to ACHI for best performance and for TRIM support, and if you install your windows from your old drive in IDE mode, you might encounter problems when booting into windows using your SSD when configured as ACHI.