Warning - not allowing the lamp to cool before turning the set on can damage the lamp
Now that we have that out of the way (you will see why soon) we can discuss resetting the lamp timer. I like to cheat (or call it being lazy) so I modify the procedure somewhat. Also, please note that the 2/5, 1/4, and 3/6 keys when in the service mode are pairs (one forward, one back in that capability). So here goes...
If the TV is ON
use Power->Display->5->Vol+->Power (within 5 seconds or you will be past the time the lamp is left on when power is pressed which would be bad
- so practice if you want to try this method <- see warning above).
If the TV is OFF
use Display->5->Vol+->Power (again within 5 seconds, but the results are only slightly bad - you have to wait, or do the above dangerous method to achieve service mode).
You should now be on the "Version Page" of the service menu.
Press Jump 3 times. It is a loop, so if you mess up, just keep hitting jump (slowly) until you see the screen says "DEM SERVICE". It should go through QM, WEM version, DEM and then back to the main version page. Once you are on the DEM page go to the next step.
Press "5" 3 times (this is another lazy thing). You should now be on number 13 which is the "LAMP TIMER" section. You could of course press "2" 12 times (the manual mistakenly says 9 times). If you go too far, remember the other key and go back (this is the 2/5 pair we are working with now).
Press "1" one time ("4" to go back, but there are only 3 items in this loop). You should now be on the LAMP TIMER RESET line which resets the lamp timer. so at this point you should be on a screen which looks something like:
2 LAMP TIMER RESET 0
Note: Due to firmware variations you may need to modify the steps somewhat, or the screen may look slightly different.
OK, if you got this far, you are ready to reset the lamp timer. Press "3" one time and the "0" should change to a "1" ("6" puts it pack to "0" - remember the number pairs). Once you have the lamp timer reset set to a one, press "Muting" and then "Enter" to save it. You can now go back to the lamp timer menu ("4") and it should read 0 now.
Almost done now. So you can either be lazy like me and press "Power" twice (about 1 second apart) and continue to use your TV as it was intended, or you can just Press Power once, and then wait 45 minutes or more to let the lamp cool down before you turn it back on.
I suggest you print this out, and practice it in your mind a little before doing it. Practicing the "going into service mode" in another room is also a good idea (no exploding lamps please). It really is not that difficult for the technically inclined, but if you do not feel comfortable doing it (if you can change the lamp, you should be able to do this), then please
call a professional and let them do it. I would hate someone to damage their expensive TV (though I do this all the time and calibrators do it every day).
As far as cleaning the optics, I can be of no help there. I would be very careful though since some optics have coatings which can be damaged, there is quite a bit of heat involved in that area, etc. In other words, a good camera cleaner would probably work, but be sure to read up on it, and look around the Wild Wild Web for information