It’s not the size of the block that matters, it’s what you do with it…. 😏
Hash rate refers to how many hashes you can produce per second. It’s a measure of total power needed to solve for the hash of a block.
Once a miner solves the hash, they get to add the next block.
Blocksize essentially refers to the number of transactions you can fit into a block. That can be done rather instantly, it doesn’t really take any extra time to fill a 1 MB block vs a 2 MB block. It does take extra computational power to go through and validate the transactions, but not to solve for the hash itself. Shouldn’t affect hash power.
Some people think we should have large blocks so the network can scale by handling more transactions… the problem is, that weakens the security of the network. It allows for a greater DoS impact, it makes mining a little harder for individuals, it’ll make nodes require significantly more storage, and all of that pushes the network towards centralization.
Only thing you really need to know, though, is that it this failed in the past.
If you want to know more about how this stuff works, start at the 99bitcoins channel to make sure you have a solid understanding of mining, and then read the Blocksize Wars by Jonathan Bier.