I'm using XP right now but most of fellow troops have Vista on their laptops, they all have recommended to me that if I were to go with Vista then get anything over 1GB to handle at a decent speed. I've played around with Vista and to me it seems ok. I didn't like XP at all when it came out but I got use to it.

As far as importing MS files and other files of that sort, its ok. I'm using MS Office 2003 on my laptop and send reports/documents to MS Office 2007+ and nobody has any trouble reading them.

Good luck!
-Mike