Actualizo: Esto ya es el colmo.
Esta tarde a las tres o así quito el Ubuntu de prueba. La parienta dice que no se puede hacer nada con el que no sabe como manejarlo. Así que le pongo de nuevo el Vista.
Pues son las siete de la tarde y todavía no se ha colgado el jodío, sólo una vez, pero lo mas bonito de todo es que... Ha vuelto a los pocos minutos!!! Cosa que hacía días que cuando se colgaba ya podían pasar horas que no volvía en si más.
Y he estado navegando a tope, jugando a los juegos Flash de la red, mi parienta ha tenido una conversación por Skype y... no se ha colgado el jodío.
A mi que me lo expliquen.
Saludos y gracias a todos por los consejos.

----------------------------------------------------------------------------
CrystalDiskInfo 4.0.1 (C) 2008-2011 hiyohiyo
Crystal Dew World :
http://crystalmark.info/----------------------------------------------------------------------------
OS : Windows Vista Home Premium Edition SP2 [6.0 Build 6002] (x86)
Date : 2011/06/14 19:36:23
-- Controller Map ----------------------------------------------------------
+ Controladora estándar PCI IDE de doble canal [ATA]
+ Canal IDE (0)
- ST3400820AS ATA Device
+ Canal IDE (1)
- HL-DT-ST DVDRAM GH22NS40 ATA Device
+ Controladora estándar PCI IDE de doble canal [ATA]
- Canal IDE (0)
- Canal IDE (1)
+ AU2FPPE8 IDE Controller [SCSI]
- ELWR W927S12 SCSI CdRom Device
+ A7J96DZ7 IDE Controller [SCSI]
- JKFWF ZG1UNOTIVW SCSI CdRom Device
- JKFWF ZG1UNOTIVW SCSI CdRom Device
- JKFWF ZG1UNOTIVW SCSI CdRom Device
- JKFWF ZG1UNOTIVW SCSI CdRom Device
- JKFWF ZG1UNOTIVW SCSI CdRom Device
- Iniciador iSCSI de Microsoft [SCSI]
-- Disk List ---------------------------------------------------------------
(1) ST3400820AS : 400.0 GB [0-0-0, pd1]
----------------------------------------------------------------------------
(1) ST3400820AS
----------------------------------------------------------------------------
Model : ST3400820AS
Firmware : 3.AAD
Serial Number : 9QH0ANMM
Disk Size : 400.0 GB (8.4/137.4/400.0)
Buffer Size : 8192 KB
Queue Depth : 32
# of Sectors : 781422768
Rotation Rate : Desconocido
Interface : Serial ATA
Major Version : ATA/ATAPI-7
Minor Version : ----
Transfer Mode : SATA/300
Power On Hours : 22234 horas
Power On Count : 1493 veces
Temparature : 44 C (111 F)
Health Status : Bueno
Features : S.M.A.R.T., 48bit LBA, NCQ
APM Level : ----
AAM Level : ----
-- S.M.A.R.T. --------------------------------------------------------------
ID Cur Wor Thr RawValues(6) Attribute Name
01 117 100 __6 00000757F10E Tasa de errores de lectura
03 _93 _93 __0 000000000000 Tiempo de arranque
04 _99 _99 _20 00000000059A Nº de ciclos de arranque/parada
05 100 100 _36 000000000000 Nº de sectores reasignados
07 _88 _60 _30 00002998CB09 Tasa de errores de búsqueda
09 _75 _75 __0 0000000056DA Horas encendido
0A 100 100 _97 000000000000 Nº de reintentos de giro
0C _99 _99 _20 0000000005D5 Nº de ciclos de encendido del dispositivo
BB 100 100 __0 000000000000 Reported Uncorrectable Errors
BD 100 100 __0 000000000000 High Fly Writes
BE _56 _50 _45 00002C1B002C Temperatura del flujo de aire
C2 _44 _50 __0 00110000002C Temperatura
C3 _69 _55 __0 000003FD1CA4 Recuperación de errores hardware ECC
C5 100 100 __0 000000000000 Nº de sectores pendientes
C6 100 100 __0 000000000000 Nº de sectores no corregibles
C7 200 200 __0 000000000000 Número de errores CRC UltraDMA
C8 100 253 __0 000000000000 Tasa de errores de escritura
CA 100 253 __0 000000000000 Errores de marca de direccionamiento de datos
-- IDENTIFY_DEVICE ---------------------------------------------------------
+0 +1 +2 +3 +4 +5 +6 +7 +8 +9 +A +B +C +D +E +F
000: 0C 5A 3F FF C8 37 00 10 00 00 00 00 00 3F 00 00
010: 00 00 00 00 20 20 20 20 20 20 20 20 20 20 20 20
020: 39 51 48 30 41 4E 4D 4D 00 00 40 00 00 04 33 2E
030: 41 41 44 20 20 20 53 54 33 34 30 30 38 32 30 41
040: 53 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20
050: 20 20 20 20 20 20 20 20 20 20 20 20 20 20 80 10
060: 00 00 2F 00 40 00 02 00 02 00 00 07 3F FF 00 10
070: 00 3F FC 10 00 FB 01 10 FF FF 0F FF 00 00 00 07
080: 00 03 00 78 00 78 00 F0 00 78 00 00 00 00 00 00
090: 00 00 00 00 00 00 00 1F 05 06 00 00 00 48 00 40
0A0: 00 FE 00 00 34 6B 7D 01 40 23 34 69 3C 01 40 23
0B0: 40 7F 00 00 00 00 FE FE FF FE 00 00 D0 00 00 00
0C0: 00 00 00 00 00 00 00 00 90 B0 2E 93 00 00 00 00
0D0: 00 00 00 00 40 00 00 00 00 00 00 00 00 00 00 00
0E0: 00 00 00 00 00 00 00 00 00 00 01 00 00 00 00 06
0F0: 00 04 00 00 00 00 00 00 00 00 00 00 00 00 00 00
100: 00 09 90 B0 2E 93 90 B0 2E 93 20 20 00 02 02 B6
110: 00 02 00 8A 3C 06 3C 0A 00 00 07 C6 01 00 08 00
120: 13 14 12 00 00 02 00 80 00 00 00 00 00 A0 02 02
130: 00 00 04 04 00 00 00 00 00 00 00 00 12 00 00 0B
140: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
150: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
160: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
170: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
190: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
1A0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
1B0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
1C0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
1D0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
1E0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
1F0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 E6 A5