Katrina,
I am a Landman with over 30 years experience, an active mineral owner and a Mineral Manager with clients who's interest I represent in negotiations with E&P companies, so I have experience on both sides of this fence. My first word of advice is "do not accept a lease form with a two (2) year option". This is never in the best interest of the mineral owner as chances are extremely high that three years from now should your acreage become open it will be worth much more than the Bonus you will be paid today so why lock yourself into a Bonus rate below the market rate at a later date. Moving on, as to whether this is a fair offer a number of the people on this board have given you some good advice and tips as to how to research the value, but unless you wait until your interest is Force Pooled and the Landman handling the area has to testify as to "the best terms given in the area" you may not really know for sure. The Landman who contacted you is probably being truthful when he told you he could not say who he was leasing for in this area. This is could be for several reasons, first, many companies want to keep their names quiet so as not to attract unwanted competition in the area and second, larger companies realize that should their name become known many mineral owners will assume that they can get a better offer (bonus amount, royalty ...) simply because the company has deep pockets. Your best course of action is to continue to ask questions as you are doing and use the OCC and other websites to investigate as best you can what recent drilling and production activity has taken place in the near vicinity. If you can access recent Force Pooling Orders in the area they will give you a very good idea as to what terms are reasonable for your acreage as well. More than likely the Landman who contacted you is a Field Broker hired by the Company who will actually drill the well(s) and he has been given the parameters under which he can take a lease from any mineral owner, that is to say he has no authority to negotiate the Bonus, royalty or lease form with you without first gaining permission from the company Landman who hired him or his company. The more knowledgeable you are and the more informed the kind of questions you ask him will put you in a better position to actually talk with someone who can negotiate directly with you. There is no hurry to make a decision to lease or not regardless of the terms being offered, however you do run the risk of the company "pulling back" due to internal budget considerations, having drilled recent dry holes or just disappointing well results which may cause them to withdraw from the area and rescind their offer to lease your interest. In which case you would be out the bonus money and have to wait some unknown period of time before the area becomes active again by this company or someone else. I would also say that in most situations in Oklahoma I believe it to be in your best interest to lease versus being Force Pooled. You can control more parameters in a lease form (such as a depth severance) that are not addressed or ambiguous under current Force Pooling statutes. Some will debate me on this particular issue, but that is my opinion based on experiences good and bad. I hope this has been helpful and answered a few of your questions.
Good luck.