Short block is an automotive term describing a bare engine including the block, crankshaft, and pistons, but not including the head, manifolds or any accessories like alternator or power steering pump. May or may not include camshaft. The camshaft will probably be included if the engine is a pushrod design and will not be included if it uses an overhead camshaft.

In other words, a short block is only the "bottom end" of the engine

Long block is an automotive term describing a bare engine including the block, head, valves, crankshaft, camshaft, and pistons, but does not include the manifolds or any accessories like the alternator or power steering pump. May not include the oil pan or valve covers.

Really depends on what your overall goal is going to be. If you just want to get it fixed for now and save your money, fix the H23. If you want performance it can go either way but most like the H22. If you want a good bit of ideas check out www.Honda-Tech.com and just read.