Upgrade current or add Second?

Hello and Thank you in advance for your assistance in my decision making process.

What i currently possess:

24"
1920x1200
lcd monitor
approx. 1 year old
(I will get back to you with more details when I get home...I'm on my laptop in school right now)

What I use it for:
Heavy Gaming (mostly L4D, TF2, Oblivion, FO3)
Heavy movie usage (currently no blu ray, but thats in the works for the next month or two)
School work (I'm a Computer Science major so I do a lot of programming)
Some TF2/L4D mapmaking (I'm really just starting to get into this, that's why its on the bottom)

What I want:
To be able to combine any combination of 2 or more of the above tasks at the same time without playing/watching in window.

Option 1:
Use my current monitor for gaming and get a second monitor to use for watching videos/internet/other. This option would save money, but would mean that I don't get a better picture than what I currently have.

Option 2:
Get a new monitor with a better picture quality than the one I own (not that the one I own is better, but it is a year old and wasn't the best one available when i bought it).
This would cost more, but would give me the best picture quality available.

I am looking to spend between $150-$250 for option 1 and $300-$400 for option 2.

Also I currently have a core i7 920 overclocked to 3.66 and a (single) gtx 260 core 216, but I am planning on upgrading to either a gtx 285 or a 5xxx ATI or gtx 3xx when they are released depending on price/performance/value.

Again thanks for the advice and if I could get you to provide suggestions for both options (i.e. links to possible purchases) that'd be great...mmmkay? (office space FTW!!)

kthxbai