OS for new system?

I recently finished building my new rig, and now I'm ready to buy the OS and get up and running.
Now.....the guys at the local computer parts shop have confused me a bit.

I had pretty much decided to go with Vista Home Premium 64 for these reasons: ultilizing all 4 gigs of ram installed, and I just can't see spending $185 for Vista Ultimate to use it for a year until Windows 7 is released.

One of the guys is telling me that I should just go with Vista 32bit because the ram limitation was resolved with the release of SP1, and also to avoid the extra issues associated with 64bit. (drivers, older programs, etc.)

I've read many threads on ram limitations, but need to know the bottom line: I know that Vista SP1 32bit will show 4 gigs of ram installed, but does it use the full 4 gigs? (Same guys at the shop say that 32bit will use up to 8 gigs)
Secondly...it seems lots of people are using 64bit Vista, and my new system probably won't be running older programs, and all hardware is fairly new, so doesn't it make better sense for me to go with 64bit?.....and does the DVD drive care as far as 64bit goes? (will it work)
Someone please help me decide which way to go, so I can get on with it!
Thanks very much..

Hardware in this system:

790i Ultra mb
4 gigs ddr3 ram
Creative X-Fi Fatality Pro audio
GTX 280 (gig of vram)
Asus DVD-RW drive

Did he tell you he wrote Vista too?

The only thing they fixed with SP1 was a display of the available memory. That's it.

32bits will support only 4GB max minus memory of the video card, bios, ... resulting around 3.2GB.

If you buy the retail version, you can have both 32 and x64 version (Ultimate has both CD and must order the x64 from M$ for 12$).
So, you could start with the x64 Home Premium and see buy yourself.

Really, you should be fine with a new build, unless you have weird hardware.

Anyway, it's what I have and really happy. 32bits apps/games working great.

The only things would be your creative sound cars. Creative are crap and not sure about the
latest driver for x64 if working fine. Do some research for that. I'm using the onboard (Realtek).

Get from a friend a copy of Vista x64, install it without the CD Key and try it. If fine, just buy a copy
and enter the CD Key and activate it. No need to reinstall.

loneeagle speaketh the truth and the guys at the shop are idiots!

No Microsoft CONSUMER 32 bit OS will use your full 4 gig of RAM. Vista SP 1 will DISPLAY the correct amount of RAM installed but it will NOT use it and you can take that to the RAM bank. We have discussed that issue here and at other boards a thousand times and trust me it is true. The amount of RAM you will use is going to vary from as high as about 3.2 to as low as about 2. With your video card you will probably have less than three. The reasons for this are complex but a quick search on the subject will quickly tell you all you need to know.

MS server 32 bit OS will use more RAM but not Vista or XP.

Home premium or business 64 is the ticket. The days when drivers and programs were a problem are over, as long as you are using relatively modern hardware and software, there are a few exceptions here and there, Cisco VPN clients for one, but most of us gamer/enthusiasts are using 64 now and we love it.

Thanks very much for the replies. I ended up installing Home premium 64 bit, and everything seems to be all good.