It ended up I had a mixture of not resetting my serial interrupt flags and the problem described in the errata link provided by Lee. It is now working 100%. All I had to do was clear the serial flags and I eliminated the x variable and now everything seems to be working fine. Even the leds indicating external interrupt 0 and 1 are now working like they should with no anomalies.

I would like to thank everyone for their input here and helping me figure this one out. Now I have just that much more hair to pull out next time. ;-)