The wallet itself is still downloading the block and is 3 years and 29 months behind. Does this mean I must wait until this finishes before it shows up?
Yes, in order to understand the current state of the network (which includes the transaction that you received funds in), your node will need to work through the blockchain history. Otherwise, your node will be unable to determine whether or not a transaction you receive is in fact valid.
Once synced with the network, your balance should display correctly.