So i plan to get myself a GTX 260 from Nvidia to replace my XFX 9800 GT. I currently have an Intel E7300 and 4Gb of DDR2 800MHZ.

Is the upgrade worthwhile, meaning will there be a very noticeable and significant increase in performance? I currently game at 1680x1050 since I own a 22" LCD monitor. Should I just go for it and sell my old card to get a new GTX 260?

It's been mentioned before already, so I won't take any credit for what i'm about to state. That being said, if you take a look at all the names/titles of each chapter, and take the first letter of each of the 12 chapters, it will spell out what I think is the bottom-line in regards to Nicole.

For everyone's convenience here it is:

Chapter 1: New Arrivals
Chapter 2: Intensive Care
Chapter 3: Course Correction
Chapter 4: Obliteration Imminent
Chapter 5: Lethal Devotion
Chapter 6: Environmental Hazard
Chapter 7: Into the Void
Chapter 8: Search and Rescue
Chapter 9: Dead on Arrival
Chapter 10: End of Days
Chapter 11: Alternate Solutions
Chapter 12: Dead Space

Regarding the movie prequel, it is good in the sense that it provides a decent backstory to the game. IMO, it's better to have played the game first then watch the movie as opposed to watching the movie first and then playing the game. The movie taken by itself though, is not really that good. Animation is quite antiquated and there's not much detail in the art. It looks like a cartoon from the 80's. The art design could have been intentional, but it still doesn't appeal to me.

That is quite puzzling. It could be possible that the Windows update that screwed everything up, needs updated drivers for your other hardware. Specifically your motherboard and video card. As far as your post says, games are the only thing not working right? So, I would suggest trying new video drivers first with the updated Vista. It's just a suggestion so I won't make any guarantees. It's just a step in trying to narrow down the possible culprits for your dilemma. I'll be awaiting any updates from your end.