Cpu usage high and freezing

I have noticed that Windows Media Network Sharing Service (WMNSS) is running between 30 - 48% of my CPU all by itself. Last night I had absolutely nothing running and wanted to watch a DVD on my computer. I had watched one already but when I stuck the next one in, the CPU jammed itself at 100% and the computer became unresponsive. I tried to shut down processes that were unnecessary, but all this did was make the situation worse. The last thing I did was try to stop services on the WMNSS then the computer pretty much froze. I would have to force a logoff and each time I started the task manager or even clicked the START button, it would just freeze again.

I finally resolved this issue by restart--> going to msconfig-->shutting down a bunch of useless start-up items-->and making the start-up of WMNSS manual along with a couple other services.

Now my CPU is at 8 - 10% on the low end but the performance monitor is still showing heavy spikes in CPU usage every second. At least it is only a quarter of what I was getting, but it still is indicative of some kind of stability issue in the system. DPC Latency Checker is showing 200 µs upwards of 321 µs upon start-up of this (DPC) program. Looking at processes in order of CPU usage, I noticed how 4 - 5 processes are jumping all over the place in %. AVG firewall services are going from 0% up to 46% back down to 2% and so forth each tick. This is not the only process doing this. And no its not a firewall incompatibility issue. It is the only firewall/AV I have running.

Running an intel dual core processor with 6GB RAM on a 64-bit brand new computer, I should not be having an issue.

I'm hoping someone may have a permanent fix for this that creates a more stable environment.