Hi, Sam -
I'm not an Attorney and If you have questions about your options suggest that you contact one that specializes in oil and gas matters.
Having said that, the following is what I understand your situation is:
You are a fortunate man. LaSalle County is in the heart of the Eagle Ford Shale play in South Texas, possibly the largest and most prolific oil and gas play that any of us will witness in our lifetimes. Even a small amount of mineral interest in LaSalle County has the potential of making you a much wealthier man.
If you do not lease, you do not receive any Bonus or Rentals.
Leased or unleased, if your land lies within a producing unit, you are due your proportionate share of the production. They pool the lands, not the interests.
If you do not lease, however, you will become a Working Interest partner in the well and liable for your proportionate share of all of the expenses incurred in developing the unit: Lease, Land, Legal, Drilling, Completing, Construction of Infrastucture, Maintainance, Re-Completing, Re-Fracking the well(s) over time, things you can't even imagine.
They will send you a series of Authority For Expenditures (AFEs) setting out what your share of the expenses are and for what. You can choose to pay them, as an active partner in the development of the unit, in which case you will also receive the amounts payable towards your percentage of the unit once production is established.
Or you can choose to go "Non-Participatory" and not pay the AFE(s), in which case any income attributable to your interests goes towards paying your share of the expenses. You will be allowed to chose whether to participate of not in each well, as they are drilled.
If you choose to go Non-Participatory, however, in Texas the law allows them to charge you a 200% penalty, so you won't see a dime until the companies that did put up their share of the risk money receive twice the monies attributable to your Non-Participatory Working Interest back.
That's 2 times "Payout" and by THEIR accounting methods...
Oh, and you'll have to carry one hell of an insurance policy, pay for an Accountant that specializes in the oil and gas industry and probably an Oil and Gas Attorney as well (You can get your lunch eaten just by the Operating Agreement alone).
Unless you are either extremely experienced in the oil and gas industry or extremely wealthy and ready for one hell of a new adventure (and possibly stress-related illnesses), I'd advise you to lease your interests.
And, for reasons I don't have time to go into today, if one of the companies is Chesapeake, I would extremely strongly advise you to go with the other. Any other company. I'll even help you find another.
If you will send me your legal description, I will take a look at the area and tell you what is happening.
Send me a copy of your lease and I'll take a look at it, too. Have you included a Pugh Clause? Depth Severance Clause? Free Royalty Clause? Environmental Indemnity Clause? Lots to consider in negotiating one.
You have to accept me as a Friend on the Forum for us to share contact information, so look for my invitation.
Hope this helps -
Charles Emery Tooke III
Certified Professional Landman
Fort Worth, Texas