Breaking a non-compete, non-disclosure employment service contract

My employer is a Philadelphia based company. It does not have an office space and allows the employees to work from home. I was hired in November 2009 and was made to sign a non-compete, non-disclosure contingent employment service contract LOU, which I did.
Back then, I was working as an unpaid intern with another employer and since this was a work-from-home set up, the new employer and I had a verbal agreement that I could work at the other firm for the months of November and December. I want to leave this new employer and work at the firm I was previously associated with as they have considered providing an employment extension. Various other reasons for my resignation:

1) The NDA/non-compete letter is unreasonably restrictive. The employer offered just $5/month as a fee (which are still unpaid) and also proposed a salary structure, which would hold true after 18 months, only if all goes well!!
All other business expenses (travel, mobile for cold calling etc.) are non-reimbursable and are to be bore by me - so far have spend more than $200.
2) The non-compete clause restricts me to work with any other firm on Wall street for a period of 5 years!!
3) This employer constantly demanded me to obtain proprietary data from my previous employer (where I interned), which is the prime reason of my discomfort.
4) Finally, despite of the fact that the company is Philadelphia-based, the contract states that in case of any disputes the matter will be handled according to the law of the state of Delaware and be resolved at a court in Delaware!!! This is totally ill-logical and a tactic to keep the employees under control because I think that such contracts do not hold valid in the state of PA.

I offered my resignation at the firm and they did not acknowledge it. They decided not to relive me of my contractual obligations clearly trying to ruin my career.
How do I make sure that all my contractual obligations have ended? The employer is not willing to end my contract which has prompted me to break it but the employer now holds a grudge and wants to hinder my career growth.