Well the SSD has arrived.
I've downloaded Win7 64bit ISO and created the boot disk on a new 4gb USB. I had an issue creating the bootsect from a 32 bit machine but found a 32bit bootsect and was able to get it working the second time around.
I've backed up everything, I think
So tonight/tomorrow I'll replace my HDD with the SSD, put in the USB and boot off it to re-install Win7 as 64 bit.
My new RAM hasn't arrived yet, and neither has the case for the SATA drive which will allow me to put it in the DVD slot, but I can still re-install Win7 as 64bit on the SSD for now and put in the new RAM when it arrives.
Wish me luck!