If you have brought a server with 1GB of RAM, I expect you are wanting it to handle some serious hits? Either that or you need it to do lots of background work.
If you need maximum performance, you should certainly consider using RAID0. However, using a simple RAID0 with 2 drives is likely to cause you serious operational issues. Both disks are susceptible to failure and if one goes down, so does your server. So unless you have multiple servers with replicated data, this is not wise.
Then again, a single drive is not wise either for the same reason. No resilience.
What you really need is to understand what level of resilience you need to design for and how valuable your service will be. If you need 24x7 operation and a server outage will cost you $000's per hour then you really need a lot of resilience. If you only earn a few $ per hour then you wont be wanting to pay for resilience.
The other question you haven't given us a clue to is how much data do you need to store? If you only need a few hundred MB, then I'd suggest two disks with RAID1 rather than RAID0. Then invest in the service over time and end up with RAID0+1 or some other more resilient combination.
Noise shouldn't really be an issue with a server, it should be in an air-conditioned separate room anyway.
Power and heat are related of course but without understanding where you will be installing the server and what else will be in the same location, it is impossible to evaluate. I would say that 1 extra disk isn't going to make a lot of difference unless you are really installing 20 of these servers?
Don't forget the decreased reliability of RAID 0 - you have two drives that can fail instead of one. – Bert – 2014-02-16T17:13:52.437