Originally Posted By: tanstaafl.
So, now the question(s). Would I see significant performance improvement if I replaced my C: drive with a 128 GB SSD drive?

It should make it faster for most cases.

Originally Posted By: tanstaafl.
Can I even do that, since my C: drive is an IDE drive?

Yes but you'll most probably need to get a bracket to make it into a 3.5" sized drive since consumer SSDs are generally 2.5" laptop drive size.

Originally Posted By: tanstaafl.
Would it be possible to replace the C: drive without having to re-install Windows and all my software?

Vista won't like you moving to a new drive and will most probably require reactivation over the phone.

Originally Posted By: tanstaafl.
If I did have to do that, would it be better to replace my 32-bit Vista with 64-bit WIndows 7?

The benefit would be that you can use more than 3ish GB of memory that is the limit for 32 bit operating systems. The downside is that all your drivers for your hardware need to be 64 bit. If a 64 bit driver doesn't exist then it won't work.

Unless you really need that missing 1 GB of memory, I'd say stick with 32 bit Windows.