I have a philips PC which had a ECS motherboard. 2 x 250GB SATA HDD's and 2 x 1GB DDR2 RAM
I changed the motherboard for an ASUS P5B-VM SE and installed new RAM (2 x 2GB DDR2)
When booting up I originally got the message 'missing operating system'
I changed the Boot priority in the bios to the other drive and got a message like drivers not installed or something along those lines. I am currently trying Startup Repair by using the recovery disc for Vista but its been going about 20 mins and nothing has happened.
Even if theres another option I guess reinstalling your system on a new motherboard is the best way forward. Bear in mind that if your system is an OEM then you might have a problem with licence. No idea how long installing of vista takes, XP pro its around 1hr so i assume on vista a bit longer perhaps? :]
Yes, you can plug them to any pc and you can access your data. And yes, you can do just as you thought, just remember that partition that you wil install your system onto will be formatted, so any data you have there(like stuff sitting on desktop or in My documents etc.) will be lost. But if all you need is on your second drive than just go ahead