On Friday afternoon at ~1pm I'm arriving at LHR Terminal 2 (SAS flight from ARN).

I'll have a small backpack and a rolling suitcase (non-rollaboard).

Just wondering which of the two rail options is better for getting into London. It looks like the Underground is a shorter walk, but a longer journey.

Heathrow Express looks like a shorter journey, but also looks like a longer walk from Terminal 2 to get to the train.

Which is a better option?

My final destination is a hotel near ExCel London on the DLR.

Thanks in advance.