Ok I've got $300 to spend on my pc and I've got some choices:

1)nice 22" widescreen lcd
2)Core 2 Duo
3)8800 series graphics card


My current system is a Dell XPS 600 w/
2.8 gz Pentium D (dual core)
2 gigs ram
(2) 6800's in sli
19" crt monitor

I play guild wars, lotro, mythos, and rts's

Given my current setup, what do you think would be my best upgrade?

are you sure your mobo will support a core 2 duo? if it does, my vote would be for that, but for me, eye candy is just a bonus... high fps at low eye candy is better IMO. Some people perfer the better eye candy.

22" monitor will only make fps worse, so rule that out.
Depending of ur system a C2D chip may require new mobo, ram, psu. U can OC the D series quite well (as long as u can keep it cool).
That leaves a new xgf card. If u do a lot of gaming (which i assume u do given u run sli) id say an 8800GT would be your best bet.

If your 19" is a 4:3 then going to a 22" wide screen won't really do too much for you (measure the viewable area and compare). As for the rest are you really having any bottlenecks? If so upgrade that particular component. Personally I loathe spending money upgrading old components, IMO I would get a quad and a 8800GT. Work out what you might get for the old computer and maybe with a small loan might be able to get a new machine.

GPU 1st, then CPU.

You might need a new power supply with a new GPU.
Tell us what you have.

Definelty buy a new GPU. Even an 8800GT will just spank the SLI setup you have now. For $300 I would pick up 2 -9600GT's and SLI them.
As for the CPU, I seriously doubt that a core duo can be installed into your rig. Before you think about that, call Dell and see what they say.
You have a decent monitor now.

order... no matter what the system is

gpu

monitor

cpu

Thanks for all the responses!

My power supply is 650 watts and my motherboard supports lga 775.

Your power supply can support the new video card.