Yes I would say as long as it was the same type and speed of memory it should work. Some memory suppliers offer a guarantee that RAM will work with a specific system (or no quibble refund if it doesn't!) if you use their memory selector tool. Crucial is one company that does this.
Timings are kind of complicated - I would suggest having a read of this article which gives some explanations. In general, lower timing numbers equal lower latency (latency being the time the CPU has to wait doing nothing while information it needs is retrieved from the memory), but they need to be considered along with the memory speed also.
Dual channel is simpler to understand. Most CPU's have dual channel memory controllers which means they can interface with two banks of memory at the same time. This should increase system speed as it theoretically doubles the memory throughput. For this to work there needs to be a minimum of two memory modules installed.