@vsipinien:
try to look in the windows event manager for those error reports and blue/black screen reports it tries to send and post them here - but most likely it is some piece of hardware failing
I tried to look for error logs, but first of all I was supprised that there seemed to be very few related to the Civilization. Considering that it has crashed so often recently I would have expected many more, but perhaps it has usually crashed in a way that has left no trace to the event log.
I managed to find few, and the following is example of those:
Faulting application civ4beyondsword.exe, version 3.1.3.1, faulting module civ4beyondsword.exe, version 3.1.3.1, fault address 0x002a9fc0.
For more information, see Help and Support Center at
http://go.microsoft.com/fwlink/events.asp.
0000: 41 70 70 6c 69 63 61 74 Applicat
0008: 69 6f 6e 20 46 61 69 6c ion Fail
0010: 75 72 65 20 20 63 69 76 ure civ
0018: 34 62 65 79 6f 6e 64 73 4beyonds
0020: 77 6f 72 64 2e 65 78 65 word.exe
0028: 20 33 2e 31 2e 33 2e 31 3.1.3.1
0030: 20 69 6e 20 63 69 76 34 in civ4
0038: 62 65 79 6f 6e 64 73 77 beyondsw
0040: 6f 72 64 2e 65 78 65 20 ord.exe
0048: 33 2e 31 2e 33 2e 31 20 3.1.3.1
0050: 61 74 20 6f 66 66 73 65 at offse
0058: 74 20 30 30 32 61 39 66 t 002a9f
0060: 63 30 0d 0a c0..
Perhaps it is not even related to the problem that has occured most often (black screen and apparently totally unresponsive computer).