My advice:

Get a desktop and then come back for more advice.

I really hope that you are joking....

I used Vista Beta and RC1 and have run it on my laptop and gaming rig since the day it released to retail.  Except for video card drivers for the first couple of months, I've had no problems with it whatsoever, even for gaming.  I just built two computers for my friend's music studio and against my advice, he wanted Vista.  I said he shouldn't get it because of all the cutting edge music software he's using.  (Cubase 4, Sibelius 4, Kontakt Player, etc.).  But even in that situation, everything is running great with zero problems. 

Vista is gaining steam as people are realizing that time and SP1 have fixed a lot of its problems.  Sales of the 64 bit version especially have all the sudden gone through the roof.  If you haven't tried Vista LATELY, you have no reason to complain about it.

EDIT:  BTW, recent benchmarks have shown there is now very little difference in gaming performance between XP SP3 and Vista SP1.  There is a small difference, but nothing you're going to notice in-game.

Wow, Vista with less than a gig of RAM, that's impressive.

@ Fazz, BenKenobi and everyone else naysaying laptops.

I've been playing Bioshock, Call of Duty 4, Orange Box, Mass Effect, and NWN2 using directX 10 and Vista with no more trouble than I ever had playing games on a desktop. The trick is making sure you cool the hell out of it with a cooling fan. (I use a Zelman ZM-NC2000)

Laptop relative specs:
2.2 Intel Core 2 duo
2 GB DDR3 RAM
NVidia 8600GM 256 RAM
17in HD LCD display

The OP's laptop, however, is garbage for game playing and it's doubtful he'll even be able to upgrade the video card in it, but good luck.

You should definitely upgrade, you should get a desktop if you plan to be doing some hardcore gaming, but if you need a laptop for various reasons, here's a couple coupons for a Dell XPS M1530 (not perfect for gaming, but should be able to play all those games fine with the right customization and was looking up the coupons for a friend so I figure I'll share):

0$?X8RJ0$G3XLB
Save 25% on all XPS M1330 and 1530 laptops over $1499 (before taxes, fees, shipping & handling)

K54SDRK72$L6W3
Save 20% on all XPS M1330 and 1530 laptops over $1249 (before taxes, fees, shipping & handling)

Anyways, I recently got a Dell XPS 1530 using the 25% coupon and it came out to $1100-ish with the following:

2.5ghz intel core 2 duo
nvidia 8600gt
4gigs ram

That runs Call of Duty 4 usually at 50-80 fps on optimal settings (mix of low, medium, high, and some things off, but hey, it still looks good imo) and should run all those other games.

to me, it's the gig of ram that kills this thing. I use my laptop for gaming, but typically older stuff or things that I can turn the graphics way down on, Psychonauts and Portal demo run pretty well. I'm going to heave to check out Orange Box eventually to see how TF2 and the rest of that does though

I think you need to up your ram to 2GB and change the video card to a 9800GTX and change the CPU.

I'm not naysaying laptops...I myself want to get a gaming-capable laptop for general purposes, as well as being able to play games with at least good settings if I'm ever away from home.

I'm not saying laptops can't play games, but your price-to-performance ratio with laptops compared to desktops is crap. 

Your average laptop will not be built for gaming, and you'll pay much more for a laptop such as yours than a desktop with similar specs.

For instance your laptop probably cost around $1000?  I know putting decent graphics into a laptop knocks up the price, and you apparently have a high quality screen...that adds up too.  An equivalent desktop PC would probably cost $500 including a 17" LCD.  And that's understandable, because laptops are always more expensive...they're portable and costly to upgrade, that's just how it is.

Oh I agree, laptops are very expensive if you go for gaming specs. Mine was around $1500 because I got a 3yr warranty, theft and virus protection built in as well as other non-gaming software I needed for school. I went for the most power I could afford mostly to ensure that the laptop would be up to date for the next four-five years as an undergrad.

It's worth every penny to be able to play a game in between classes, at work, or any where else with a power plug. What I understood, maybe not from your post but others, was that laptops were shit for playing games which just isn't true if you're willing to spend the money for them.