Age discrimination or ?

As a Regional Sales Manager, I was let go from my company (Philips Medical Systems North America) five and half years ago. We were downsized, managers were cut in half. Of all the regional managers I was in the position the longest. I was Regional Manager of the Year and top producer for many years. When I was let go in ~May of 2003, I was the leading also that year.

I was given a chart showing the bell shaped curve of all positions cut within the company, I guess to show how the company cut evenly across the board. Two years prior I was invited to attend a special training session, for managers and key sales people, because we were going to lead the future of the company. Basically, we were told to cut the lower 10-20% of our sales people based on performance. In addition, we were told to look at our people based on will they fit within Philips in the next 5 to 10 years.

Knowing that, I feel they looked at my position the same, at age 54 would I be around 5-10 years more? I also was probably paid the highest base salary along with commission/bonus. I was with the company 17 years. Our company Advanced Technology Laboratory, was purchased by Phillips Medical Systems ~1998.

I had to sign a letter that basically said if I were to take the severance pay (~$75,000) that I would not take any legal action. If I took legal action, I would not receive the money. They did offer that I could apply for any other position, which would have required a move to what ever position I could find (which would not be management) We also had a rule of 75, that would then also cover health care during retirement.

I did apply at several other companies, with no offers, which again I feel was based on age. So, I began selling residential Real Estate since.

My question is, can I sue for age discrimination or ? . Will it be worth my time and money or the chances are minimal against a company that is quite large?