Help me out here guys.

No matter how I try to enter Megaton, it crashes the game. If I "coc megatonplayerhouse" or "megatoncratersidesupply", I arrive in those cells just fine, but crash when hitting the door.

Here's my modlist and load order:

Fallout3.esm
Unofficial Fallout 3 Patch.esm
Anchorage.esm
ThePitt.esm
BrokenSteel.esm
PointLookout.esm
Zeta.esm
CALIBR.esm
FEM.esm
FOOK2 - Main.esm
FOOK2 - [[censored]] World And Neighbourhood Kit.esm
FOOK2 - [DIK] DLC Improvement Kit.esm
ArefuExpandedByAzar.esm
AmyWong.esm
AQFH_D.esm
ShadySands.esp
Unofficial Fallout 3 Patch.esp
Unofficial Fallout 3 Patch - Operation Anchorage.esp
Unofficial Fallout 3 Patch - The Pitt.esp
Unofficial Fallout 3 Patch - Broken Steel.esp
Unofficial Fallout 3 Patch - Point Lookout.esp
Unofficial Fallout 3 Patch - Mothership Zeta.esp
DarNifiedUIF3.esp
Auto Aim Fix v1.1.esp
ArefuExpandedByAzar-Radio.esp
Fellout-Full-1.1.18fook2alpha.esp
Fellout-Anchorage.esp
Fellout-BrokenSteel.esp
Fellout-Zeta.esp
Fellout-pipboylight.esp
FOOK2 - Main.esp
FOOK2 - [EVE] Energy Visuals Enhanced.esp
FOOK2 - [DIK] DLC Improvement Kit.esp
FOOK2 - Mothership Zeta.esp
P94-95.esp
VATS - MCE.esp
FemaleEnclaveSoldiers - Broken Steel.esp
ACE2.0b.esp
F3UmpaAnimation.esp
megalight.esp
EssentialFollowers+Caravans.esp
AmyWong - DLC01 Anchorage.esp
AmyWong - DLC05 Zeta.esp
AmyWongQ1.esp
FEM - NPC FEMinizer.esp
MergedPatch.esp

One thing I see, move your UF3P.esm down to under Zeta.esm; I usually have the UF3P's esps as the first esps loading as well. That's the first, and only, thing I spotted.
Others may have other suggestions as I don't use many of what you have

Are you using any body/armor/clothing replacers? I had this problem once and traced it back to Lucas Simms' outfit.

Yes, I'd make sure you have the latest version of Breeze' Male Bodies clothing replacer (if you are using BMB, that is), which fixes a bug with the BMB Lucas Simms sherrif's coat mesh. If not, then try disabling megalight.

If all else fails, use Fo3Edit's MasterUpdate - it resolves these kinds of crashes almost without exception.