I am sorry to hear of your loss.
Most of the advice you have read is good advice. I wanted to add a few things to be sure you're looking at it from the right perspective.
First off, you must have lived in the home for two of the past five years. This time does not have to be consecutive; you could live in the home for the first year, rent it for the next three, and then return for the final year of the five (for a total of two years lived in the home). This qualifies you for the exclusion. You must also have owned the home as your main residence (ie, not an investment property).
The exclusion is $250,000 per individual and $500,000 for a married couple. There are provisions in the tax law for surviving spouse which a tax adviser can walk you through. Regardless of what you do with the home, I would definitely recommend having a tax professional go through your current taxes as your situation has changed and (outside of the home), there may be new rules that apply to you as a surviving spouse.
As long as you continue to stay in the home as your primary residence (and have lived in it or will live in it for two years in regards to the 2 out of 5 years rule) and you don't project your profit (gain) to be more than $250,000, you really don't even need to think about it too much (other than to make sure you fill out the tax form correctly). If you plan on making more than that upon the sale of your home, then you would definitely want to sit and chat with a tax professional.
If you live in the house less than the necessary two years, there are ways to still avoid some capital gains tax (basically you are given a ratio of the time lived n the home - ie, one year lived in the home is 1/2 the necessary time, so you would get one half the exclusion - as a married couple, $250,000 or single, $125,000).
Again, I definitely recommend a tax professional - the calculation of the "cost basis" of your home isn't just what you paid for it, but the total of the purchase price, buying costs - title and escrow fees, real estate agent commissions, etc., improvements such as a new roof or a new furnace, selling costs - title and escrow fees, real estate agent commissions, etc. minus the accumulated depreciation (for example, if you ever took the office in the home deduction). This "cost basis" subtracted from your sales price (when you do sell it) is your gain (loss if the number is negative, which I hope its not!).
I know that's a lot of information, but I wanted to give you some other bits of information that hadn't been covered. I hope it helps and please remember, you're best off speaking to a tax professional on this issue to be sure you get all of the appropriate tax deductions, exclusions, etc. and make the most of your money. No one likes to give more than they have to!
I wish you the best in this tough time for you. If I can be of any assistance, just let me know.