This is from win2000 and win2003 server but is in the same regedit.exe place in win7.
This image is from a win7OS 32bit sp1, i have not tried to set it to a different place, run a test nor have i been able to find the documentation for win7.
Log file name and location information is stored in the registry. You can edit this information to change the default location of the log files.
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Eventlog
For example, if you want to move the application log (Appevent.evt) to the Eventlogs folder on the E drive, type e:\eventlogs\appevent.evt.

The event storeage site is:-
%SystemRoot%\System32\Config
If you wish to.open this you will have to download a file program to open it.
Is good for win2000, server2003, xp, vista,win7...
Copy and paste %SystemRoot%\System32\Config into 'Search programs and files' of win7 then click on the file, follow the links to the download page to use a file program to open it.
In the file association page , select from 'Sponsored sites' in the gray area at bottom.
You can also view your events logs from another computer or possibly from a live cd/dvd, i do not know if this will work when your system is playing up
Event Viewer -> Action -> Connect to another computer
Also you may wish to....
Open Event Viewer -> Action or help -> click on help, this will open the Microsoft Management Console ->
Event Viewer -> Event Viewer; 'how to...'
-> Manage event logs -> Set max. logs size.
(you may wish to make larger- default size 512kbs and then writes over itself, it increases in 64kb amounts
eg.8 x 64kb = 512kb)
also
Microsoft Management Console -> Event Viewer -> Event Viewer, 'how to ...' ->
Manage Subscriptions -> 'Work with event logs on a remote computer'
also 'Run task in response to a given event'
eg. XYZ drive stops, etc -> save to here and do not over write.
Please follow all normal regedit.exe methods and make a backup of the regedit.exe. before doing anything with it.
Hope this is of some help.