The other point is a Hunter 26 may a bit on the small side and designed for more protected waters than the trip from LIS to Block Island, or from Block Island to Buzzards Bay. Is this the Hunter 26.5 or the 260.
While the boat would probably be fine for the trip in good weather, if the weather goes south, it'd be a bit dicey. We often have SCA type weather in Buzzards Bay, and while I go out in it in my boat, my boat would dwarf a Hunter 26 in many ways.
If you're going to go anyway... I'd highly recommend getting and reading
The Coast of Summer-by Anthony Bailey about cruising New England in a Tartan 27, since it will be a good book to read and is about these waters. I'd also recommend getting
The Cruising Guide to the New England Coast.
A few places that would be worth stopping:
Cuttyhunk Island, but get there early in the day to get a spot inside.
Menemsha, Martha's Vineyard, but you'll want to anchor in the pond, since the main harbor only has two or three moorings for private boats. Draft can be an issue for some people getting into the pond at anything but high tide. Don't try making the harbor if the wind is out of the north, it can be less than fun... in that case go to Tarpaulin Cove instead.
Tarpaulin Cove, on Nashuon Island, is a great stopping place and decent anchorage if the wind is out of the North-Northwest-West. The island is privately owned by the Forbes Family Trust, but they allow the beach to be used by boaters anchored there.
Hadley Harbor, on the eastern end of Nashuon Island, is a very protected anchorage that is nice to stay at. However, Woods Hole has fairly fierce currents, so check your Eldridge's. Also, the traffic through the Hole can make things interesting for a small sailboat. I'd only recommend this if you're going up into Buzzards Bay, rather than along Vineyard Sound, since you have to go through the worst part of the Hole to get there from Vineyard Sound, but not from Buzzards Bay.
Vineyard Haven, Martha's Vineyard, is a lot more commercialized in the tourist sense, and you do have to be wary of the ferries. Anchoring on the west side isn't bad and protected from anything but a North-Northeast wind. Lots to do there if you're into touristy stuff. I'm not.
Edgartown, Martha's Vineyard, is also a very commercialized tourist trap area. Not well protected if the wind is from the north, but you can always hide in Cape Poge Bay or Katama Bay.
Nantucket is almost impossible to get a mooring or slip in during that time period, unless you get there very early. However, if you have a shallow enough draft, you can always anchor in the Head of the Harbor, where the water gets pretty skinny. If the wind is from the south, you can also anchor outside the harbor, off the beaches. The eastern side north of the harbor's barrier beach is better IIRC, than the west, which is rockier and less good holding.
If you're planning on going north, through the Cape Cod Canal to Boston, I'd recommend the following additional places to stop:
Padanaram (Dartmouth). The harbor is very shallow, so be aware of that. Also, there's a swing bridge that you have to pass to get into the main harbor. Well protected from all but South-Southeast winds.
Fairhaven and New Bedford, which have a lot of maritime related sightseeing exhibits. The
Whaling Museum in New Bedford is a particularly good one.

If you do stop in NB/FH, let me know, and if I'm around I'll take you to a few good spots.
Sippican Harbor (Marion). Good spot to stop on the way to the canal, but not a whole lot to do there.

Not protected from South-Southeast winds.
Phinneys Harbor is a good spot to stop before making the canal entrance, as it is right there at the mouth of the canal. Again, not much to do there... but well protected from most directions except West winds, unless you hide behind Toby's Island.

The other alternative is Onset Harbor, but Phinneys is easier to get into IMHO and larger.
Cape Cod Canal passage should not be attempted if the wind is from the southwest... If the wind is north or east, you'll have a much easier time of it...but with the wind from the southwest, there will be standing 6-9' waves there...and it won't be much fun or very safe. Check your Eldridge's for the currents, since the current is quite swift through the canal. Just before the Cape Cod Bay side exit, there is a small harbor (Harbor of Refuge) on the southern side. This is often a good spot to wait if the wind is out of the Northeast, since the same problem can happen on this side, but less so. They will not allow you to sail the canal, it must be done under power. IF your engine is not reliable-DO NOT ATTEMPT IT.
Provincetown or
Wellfleet are the only two harbors I'd try to stay at on the inside of the Cape. Both are fairly well protected, but Provincetown has a lot more to do than Wellfleet does.

Be aware that it's a pretty long sail for a smaller boat to go from the canal to either.
On the mainland side, you've got more options, these are two I'd recommend on your way up to Boston.
Plymouth Harbor or
Duxbury Bay are good choices if you're planning on going up to Boston. Plymouth of course has Plimouth Plantation, and the original Plimouth Rock... the rock would probably fit under my dining room table, so don't be surprised at its size.
Cohasset Harbor is a good stopping point before entering Boston Harbor proper, if the wind is out of the south. It bites if the wind is out of the north.
The Boston Harbor Islands are a state park and have specific requirements. From their
website:
Moorings: Limited docking space is available for private boats at Georges Island on a first-come, first-served basis. On all other islands, docks are available for off-loading only. Small prams are available for anchoring off-shore. For information on moorings for private boats at Bumpkin, Georges, Peddocks and other Boston Harbor Islands, Call 617-223-8666. For reservations and technical information, call 617-241-9640.
Boston, itself, you'd want to make a reservation for a slip at a marina more likely than not.
I hope this helps.