Vista can be run on that but it will not be nice to use. When compared to xp it needs more resources. Pretty=resources.(even in xp, you can get "skinning" programs that make xp look like vista, look at:
www.wincustomize.com ) 2gb of ram is going to run vista and probably only vista, especially if you want it to be pretty. You can forget about playing games on that rig while running vista unless you turn off all of the prettys 1st and then you
may have 1 gb of ram available. It would be a huge pain in the rear. On the other hand it would give you the ability to learn vista and how it differs from xp. Perhaps dual booting both xp and vista would be good for you.
There are few issues with vista anymore. Historically when you compare windows 2000 to xp the exact same "issues with resources" were being complained about. The difference being that xp is near 10 years old and vista only 2. People just accepted this and moved forward but the problems came when people had alot of money tied into peripherals that did not work well with vista. This upset alot of people that did not understand that vista has stricter software requirements and it is more secure. They wanted to still use there 5 year old camera and 7 year old printer. For a 10 year old OS xp still does the job but I prefer vista64 on a system that is built to run it.
My system is more than what is needed to get a 5.9 user rating it is a custom built desktop. There are however laptops that can and do run vista very well.
My minimum specs for a vista rig would be.
a cpu that is as close to 3Ghz as possible. (dual or quad core)
4 GB of ram (ddr/ better if it is ddr2)
100 or more GB hard drive (sata).
dvd rom
a decent dx 10 graphics card
This is my suggestion not m$. M$ is probably lower req but I know you want to run it "pretty".
Good luck.