Welcome to WW!
PointsPlus & the older Points plans (aka Momentum & TurnAround) are different from each other. The actual formulas that they use to get the Points numbers are very, very different.
It's important to know this (and hence why you asked!), because the
older cookbooks or older plan items that have Points numbers on them are going to be highly inaccurate for the purposes of PointsPlus.
Since you're just starting out, I would personally suggest going to a Meeting, even if it's just
once, to get
all the materials from PointsPlus and to hear how it works. If not, you might want to consider joining Weight Watchers Online, and using the eTools that they have available. Everything you need to know about PointsPlus is on their site, and it's the only plan that WW
currently actively supports.
If you don't want to use Online or go to a Meeting, there's actually an At Home Kit that you can order from the WW site without officially joining anywhere. (There's a Sticky for the link to the At Home Kit at the top of the WW section here.)
As someone who is just starting out on WW, having that support and the materials would be a huge advantage.
That being said. The older plans still work. They aren't suddenly broken simply because WW no longer supports them. There are many members (especially on 3FC!) who enjoy Momentum/TurnAround better and are sticking with it. They're still doing perfectly fine! Again, nothing is wrong with the older plan.
In your case, since you have many of the cookbooks, it might be handy for you to use the older plan.
But, do you have an older Points Calculator? Do you have the Plan Materials for the Older Plans? There's more to all the WW points counting plans than just counting points. There are the GHGs, and other things that go into making sure we're being as healthy as we can while also counting points.
I advise against guessing at Points in the beginning, regardless of which Plan you end up following. The Points, while somewhat near a certain amount of calories, are NOT exact, and trying to guess that in the beginning could be a detriment to your weight loss and a detriment to thoroughly understanding how the Plans work.
Neither plan is better. It's all about what is better for you.
Whatever plan you choose. Don't guess at how many Points you're supposed to eat. That's setting yourself up for possible confusion.
Either find a way to get some materials about the older plans, if you're still interested in following them. Or get an At Home Kit, join Online or join for 1 meeting at WW to get all the info you'll need to follow PointsPlus.
Whatever you decide, there are members here doing it, and we can help point you in a healthy direction along your way. Best of wishes on whichever plans you decide! ~