I have also recently swiched from XP-Pro 32-bit to Vista Ultimate 64-bit. The change for me seems much smoother, so far, than the change from Win 98 to XP-Pro. It ain't perfect, but so far, everything I was running on XP runs on Vista-64.
MS and program vendors still have work to do. Google will not remember your preference settings, Adobe reader gets confused, the venerable Winzip cannot remember that you hate to see the quick-pick in the system tray; and MS's own IE8, running in IE7 emulation, has trouble opening many web-sites, forcing you to stop/start the URL request.
Don't even try to examine an eBay feedback record in native IE8 mode. The record summary will display, but the individual item-entries will only display for a nano-second. There are certain applications [DVD Pro] that require you to launch with a right-click, then choose "Run as Administrator" from the drop-down list - if you want to write to the root of C:\ [to create/update the database backup file].
With 4GB of fast DDR2 and a dual, triple or quad core CPU of your choice, Vista flys! Photoshop type applications run much faster and you can handle larger file sizes because of having more memory and better utilization thereof. You can better handle large file transfers, to file or disc.
Media Center is built-in to Vista Ultimate and I have had no problems using MS-Media Player to play DVD's or CD's. Media Player and Windows explorer both handle burning CD's and DVD's without needing external programs. I have ROXIO 9.2 loaded, but have not needed to use it.
You never have to shutdown now, unless you just upgraded a program that needs to restart in order to register components. The Suspend-to-RAM is much better integrated than the HIBERNATE function of XP. Ten seconds to Suspend, and another ten to wake-up. With your laptop, save everything first in case of a power outage. You can conveniently set your scanning software to run scans while you sleep, then you perform the clean-up when you awaken the PC the next day.
Finally, you will be learning new skills associated with using/mastering the latest and greatest from MS. [Linux & Mac, this is a MS forum question.] Skills that will be very useful in your workplace.
Good Luck and enjoy yourself.