If it is dry, Schumacher yellow mini-spikes all round is a safe bet (remember you need to order the SLIM front for 2wd). Some drivers prefer to use a Schumacher stagger rib on the front of a 2wd, so this is also something you could try if you wished (Personally, I always use minispikes).
If it is
Slightly wet Schumacher green minispikes work nicely.
If we have had a heavier shower, Ballistic buggy minispikes in green are a better option (pink compound also works, but wears out faster
)
As for Schumacher tyres in general, I believe Blue is made from a similar "rubber" to yellows, but is a harder compound.These two are usually used in the dry.
Greens are made more of a "synthetic" material, designed for slippery/wet conditions.