[Users] The correct hardware request

Being very interested in SIP Routers and SIP Softphones is is an obvious step to SIP Servers etc. Having found OpenSER on the Web I have decided that I should at least get a system that I can run locally to use for testing kit and to demonstart to whomever the potential of SIP communication. I realise that I need a "server" and a Linux OS to run on I would be obliged if someone could advise the most reasonable lump of Hardware to use by giving a indication of say type of Processor and Memory requirements. I have to hand a Chassis that has a AMD K6-2 350 Mhz processor and 106 Meg of memory. I do also have a another chassis with a AMD K6-2 550 Mhz Processor and 256 Meg of Memory but that currently runs a test version of XP . I realise that Linus is required can anybody suggest which "version" of Linux has had the best success with OpenSER as I would like to avoid as much as possible the need to interact to much with the OS so I can concentrate on the Application more. In anticipation .................thanks Paul Coenraats Data Communications Consultant