Just curious, if you could only use one long gun and one side arm for FONV, which would you pick for beginning/middle/endgame and why? I'm thinking of doing this with my next character. I could think of a few contenders, but nothing really jumps out at me. And just to clarify, a long arm is anything that would be strapped to your back, and a sidearm is anything strapped to your hip.

That Gun, This Machine.

Varmint rifle
10mm pistol

Hunting rifle
10mm SMG

Silenced Sniper rifle
Silenced 12.7mm SMG


Brush Gun
Hunting Revolver


AMR
Sawed-off Shotgun


Your mileage may vary

I like carbine, so it is hard for me to pick a "long gun".

My side arm is a FBHT.

A .45 and a fully modded hunting rifle planty good enough to get you through the game.

Modded Hunting Rifle
Silenced 12.7mm SMG

These can carry you through the entire game.

I'm actually kind of doing this with my current character. Carrying one rifle, one handgun, and also carrying around a small melee weapon. Don't always want to waste a bullet haha.

Started off Varmint Rifle (Modded with a Scope, then a silencer later)/.357 Revolver/Knife
Then I got my Hunting Rifle, and a Sniper Rifle. But sadly the Sniper Rifle I got was at 0 condition, so it's pretty much a waste. Since I don't want to pay the 8000 Caps to repair it (Still at Novac). Also just got Lucky. Kind of want to get a .44 though, so I'll probably get that somewhat soon.
Till then I have a Hunting Rifle (Modded Scope right now)/Lucky/Combat Knife.

My final set is probably going to be Anti Materiel Rifle/Ranger Sequoia/Chance's Knife.

(edited because I reread your first post and realized I was using two of your defined sidearms.)

Starting out...
Varmint Rifle with silencer
.357 Magnum with long barrel or a .44

Then I pretty much dump handguns unless I'm going into a casino where I take the silenced .22 pistol. That was until Dead Money with the Police Pistol and even better Honest Hearts when "A Light Shining in Darkness" came about

After the beginning of the game I'm partial to the following weapons:
Primary...Sniper Rifle, Gobi Campaign Scout Rifle and/or Anti-material rifle

Secondary...Riot Shotgun, Grenade Rifle, Survivalist's Rifle(I love this rifle)

I always buy the Brush Gun for Boone to use and sometimes let him use the Anit-material rifle.

I'm doing an Eli run through right now (book of Eli that is) so I run:

A Light Shinning in Darkness
Hunting Shotgun

or

Sawed off shotty
Survivalist Rifle/Hunting Rifle

With both I have a machette gladius

Laser Rifle with scope and focus optics
That Gun (only because of Blade Runner)

EWs:
Laser pistol -> Plasma Defender
Laser Rifle -> AER-14

Guns:
10mm->12.7mm
Varmint Rifle->Ratslayer->Hunting Rifle

Automatic:
10mm SMG
Service Rifle (not automatic to be precise, but :meh:) -> LMG

Personally i always have a pistol, short range, automatic, long range and AoE DoT weapon.

(Area of Effect with Damage over Time for those who don't speak gamer :hehe:)

One long, one back up I've done a few times.
Depending on stats, role and level, Hunting rifle and 9mm; trailgun and .357. or assault carabine / marksman / service and 9mm, 12.7 smg and pistol.
Often shotgun any and any pistol.

Ratslayer / Hunting Rifle+++ / Survivalist's Rifle
10mm pistol / .45 Auto

i always do this

service rifle and 45 auto pistol

Fully Modded Hunting shotgun (prefer capacity than dmg) with 12 guage magnums
Fully modded 44 magnum with SWCs

Early - Rat slayer and Weathered 10mm

Mid - Rat slayer and modded Weathered 10mm or .45 modded

Late - All American and Light in Shining Darkness


I usually also carry Chances Knife and Lever action Shotgun (Cowboy, grunt, shotgun surgeon, hand loader, juryrigging)

A sniper rifle and a silenced 12.7 pistol. If you are stealthy enough, that is all you need (assuming you can maintain enough ammo).

I often walk around with just a rifle and a sidearm. Currently, it's the Survivalist's Rifle and A Light Shining in the Darkness. They make quite a pair, so I'll go with that.

Ranger Sequoia & Sniper rifle suppressor/carbon fiber parts

Almost my load...

Early - Rat slayer and Weathered 10mm

Mid - Gobi Sniper rifle and Light in Shining Darkness

Late - Anti-Mat rifle and Light in Shining Darkness

Oh and I also pack Chopper... not really sure why as I never use it, but I almost always have it on me.

All American + Ranger Sequoia

Brush Gun + That Gun

Either one of those works pretty Good for me, throw in Chances Knife and I'm pretty much set.

I'm assuming this discussion is only for guns and not energy weapons,

Well I'de probably carry an Assault carbine with extended mags and a 12.7 mm Pistol.

or

This Machine and a Hunting Revolver.

I usually give Boone the Gobi and the Anti has crap DPS for my tastes. The Ratslayer can kill deathclaws with 3 - 4 shots for me. My luck is 10, I have light touch, Boones beret and JG's armor add the x5 from Ratty and you crit every other shot or so, and ability for HP OR AP ammo.