The number of processes is fairly unimportant, what you need to look at is th eCPU usage of each process.
Click the CPU column in the process list so you get them ordered by CPU utilization. Then there may be a rogue process running which is hogging the CPU.
If there is, try first of all terminating that process. If its explorer you will lose your desktop but you can start a new explorer process from the applications tab by clicking the new task button and typing explorer.
14Mb for explorer is not anything unusual. My pc is currently running fine with explorer using 45Mb