I like the idea of a nice pale ale for your brew, but you might consider a yeast that is neutral and very reliable - WLP-001 or (dry) Safale US-05. This is less sensitive to process variations like temperature, and I think it is consistent even if you overpitch a bit. I've not used the dry version, but have heard it works great. You might bump up the crystal malt since this is a high attenuator. It will ferment quickly, carbonate bottles reliably and give you a clear, beautiful beer. I'd use that for a stout as well.
For sanitation, I agree with the posts about Iodophor. I keep a bucket full and keep spoons and other tools soaking until I need them. And I do not rinse before using. I actually use an equivalent product used in dairy operations, with great success. Of course focus especially on equipment that touches the wort as and after it cools from boiling (chillers, fermenters, etc). Before sanitation, you must physically clean surfaces and then, preferably, use chemicals like PBW to finish the job. Keep in mind that a smaller batch (2.5 gal vs 5 gal, for example) requires MORE vigilance since you have greater surface area per volume.
If your local vendor either moves grain quickly or keeps it in a low humidity environment with minimal air exposure, the grain should be fine. Hops are harvested once per year, so if they are packaged in air-tight containers and kept cool they are usually fine. You see lots of folks using northern hemisphere hops from fall to spring and New Zealand hops from spring to fall for max freshness. Yeast has expiration dates, which seem (to me) to be conservative. If kept refrigerated, go with the freshest liquid yeast available. Dry yeast is more forgiving, I believe, but still has a freshness date. But it all depends on how the vendor handles it. I usually buy hops online in 1lb packages, but get the rest of my ingredients locally (from a shop that handles them right).
I agree with those who suggest scaling by half for your first batch. You will have to adjust your recipes since extract from grain varies greatly depending on your equipment and process, and your mash will likely be less efficient with a less-than-optimal mash depth with a 2.5 gallon batch. You may find too that you need to adjust hopping rates or boil times to get what you want, but that sounds like fun to me.