My M-4 with M203 that I carried in Iraq in the picture above (I had that zeroed to the point that I could shoot the pecker off a gnat and had to take off the 203 and give it to another unit). For the 203 I'd have the normal H/E rounds and buckshot rounds as well as some parachute flares.
On my thigh holster I'd have the Barretta M-9
Slung on my back I'd go with a Mossberg 590
On my belt a Kukri knife (really a small Machete).
At home I'd have the M-14 with an ACOG sight.

The worst realistic weapon I'd say would be a sword... I know I'm going to draw the ire of manya WWZ fanboy here but a sword takes years of training to master and just whips blood everywhere.