Will additional memory speed up my computer?

In general yes it will speed up your computer.

Additional memory will not increase the speed of the CPU, however it will reduce the time a CPU spends waiting for information from the hard drive. RAM provides data to a CPU faster than a hard drive, so it will not take as long for programs to execute. If your system is running slow and you have less than the ideal amount of memory, -increasing the memory is an easy way of boosting system performance.