Exchange 2003 rebooted on it's own - probable problem?

Hi all ye Experts...I've got here an Exchange issue
So, here's what happened.
Our Exchange Server rebooted by itself and the only thing the system event logs say after i boot the server up is "The previous system shutdown at 9:38:19 AM on 6/12/2008 was unexpected."    and   "The C: disk is at or near capacity.  You may need to delete some files."

The Application log had these after booting up:

"The MTA is running recovery on the internal message database because the MTA was not shut down cleanly. This operation may take some time.  Status updates will be written to the Windows 2000 Event Log. [DB Server MAIN BASE 1 0] (14) "

-------------------------------
Event Type:      Information
Event Source:      Application Error
Event Category:      (100)
Event ID:      1004
Date:            6/12/2008
Time:            9:46:00 AM
User:            N/A
Computer:      PTEXCHANGE
Description:
Reporting queued error: faulting application store.exe, version 6.5.7652.24, faulting module ese.dll, version 6.5.7638.2, fault address 0x0004eaa8.

For more information, see Help and Support Center at www.eventid.net.
Data:
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 73 74 6f   ure  sto
0018: 72 65 2e 65 78 65 20 36   re.exe 6
0020: 2e 35 2e 37 36 35 32 2e   .5.7652.
0028: 32 34 20 69 6e 20 65 73   24 in es
0030: 65 2e 64 6c 6c 20 36 2e   e.dll 6.
0038: 35 2e 37 36 33 38 2e 32   5.7638.2
0040: 20 61 74 20 6f 66 66 73    at offs
0048: 65 74 20 30 30 30 34 65   et 0004e
0050: 61 61 38                  aa8    


-------------------------

Event Type:      Error
Event Source:      Application Error
Event Category:      None
Event ID:      1001
Date:            6/12/2008
Time:            10:19:11 AM
User:            N/A
Computer:      PTEXCHANGE
Description:
Fault bucket 450554334.

For more information, see Help and Support Center at www.eventid.net.
Data:
0000: 42 75 63 6b 65 74 3a 20   Bucket:
0008: 34 35 30 35 35 34 33 33   45055433
0010: 34 0d 0a                  4..    

-----------------------------

Do you think any of these indicate something is faulty with our Exchange Server?

Also - i deleted a DR Watson user.dmp file after the unexpected reboot because with that and the Exchange auto database backups it only left 300MB on the C: drive.
But there are also a couple large files that i'm wondering if i can safely delete as well...

C:\Documents and Settings\%username%\Local Settings\Temp\WER3d6b.dir00\store.exe.hdmp
and
C:\Documents and Settings\%username%\Local Settings\Temp\WER64cd.dir00\store.exe.hdmp
and
C:\WINNT\PCHEALTH\ERRORREP\UserDumps\store.exe.20080604-072638-00.hdmp
and
C:\Program Files\Exchsrvr\bin\TEMPINTEG3392.EDB
and
C:\Program Files\Exchsrvr\bin\TEMPINTEG1636.EDB

Anyone know if i can safely delete these?