I purchased a couple of years ago a Dell precision M6300 with 4 GB of Ram, Nvidia quadro FX3600, Xtreme X9000 processor but...i'm running XP32 bIT and for this reason i'm not using all the RAM i have available.
The 95% of usage of this pc is SONY VEGAS pro 10/11
I wanted to add 8gb of Ram on this pc and of course i should go for WINDOWS 7 64 BIT right? Peoplel on the electronic stores were suggesting me to purchase windows 8 that nowaday is pretty cheap and if i won't receive the benefits of touch screen or the very quick start of the system, i'll enjoy the other benefits! Would you go for W8 or for W7? Remeber that i use this pc 95% for editing with Sony Vegas.

Second question: i went on the Dell site and the RAM is very expensive; wich 8gb of RAM should i buy?

The principal of my upgrade is that my workstation is a great pc that works good for my job, now i can't afford a new workstation but...i can improve the ram and the Windows stuff, are you with me?
Guys i really wanna thank you for your help in my decisions
Many thanks