The recommended PC memory is 2 GB or more, but if you consider the acquisition load on the SMARTDAC+ GA10, would it be better to have a lot of memory?

Absolutely. However, note that if you have more than 4 GB of memory, you'll need to use a 64-bit OS for it to have any effect. If you're going to use more than 4 GB of memory, use a 64-bit OS and the 64-bit version of the software.