Not sure what manufactuers are available on your side of the pond, but Freud is always a good choice. Might be a little pricey, but the quality is very good. The blades I get usually depend on how fat my wallet is at the time. Circular saws on this side of the pond are normally 7-1/4" so you would sacrifice a lot of depth of cut going with a circular saw blade. 10" Thin kerf blades are also available, at a price.
Cutting plywood and ripping pine normally requires two different blades. When cuttting plywood you need a lot of teeth to avoid tear-out of the veneer face of the plywood. Ripping pine requires a lower tooth count for two reasons - one you are ripping the wood so you don't need to worry about tear-out and two because it's a softwood the sawblade is able to tear out larger chunks of wood - the lower tooth count allows a larger gulllet between the teeth with more room for sawdust.
If it was me and I expected to cut a lot of plywood I'd get a dedicated 10" plywood blade. A combination blade will probably serve you just fine for the rest of your cutting chores, just don't expect glass smooth cuts because the blade is a compromise between a rip blade and a cross-cut blade.
Have fun and keep your fingers away from the blade.
Don