Vehicles in MechCommander are mostly harmless, however they can be very useful in some missions, nearly essential. Additionally, in the missions, most of the enemy force (by number) us vehicles, so knowing what they are good at (and therefore how best to combat them) is extremely useful. 

In-Game Pictures of all the vehicles will be coming as soon as I have the chance, however for the moment I don't have the ability to take those pictures!

IS Vehicles 

Swiftwind Scout Car
Pegasus Light Scout Tank
Refit Truck
Minelayer
Minesweeper

Clan Vehicles

Savannah Master
Swiftwind Scout Car
Pegasus Light Scout Tank
J. Edgar Light Hover Tank
Harasser Light Missile Tank
Saracen Hover Tank
Striker Light Tank
Refit Truck
Minelayer
Minesweeper
Condor Heavy Hover Tank
SRM Carrier
Bulldog Medium Tank
LRM Carrier
Rommel Medium Tank
Von Launcher Heavy Tank
Schrek PPC Carrier

Other (Campaign) Vehicles

Armored Car
Fuel Truck