I have a number of different projects, about 5, and a number of different developers, around 15, and some of the projects are in subversion and some are not. All of the developers are working on windows-based machines with TortoiseSVN, and the code of the projects is a mish-mash of classic asp, and asp.net. What is the best, as in most responsive, useful, and easy to administer, way to have all of the projects under subversion and have authenticated access for all of the developers, both read and write?

Some of the things to consider would be to serve it out via svnserve or apache, which means there are speed concerns, ease of administering access/users & passwords, and the need to open an additional firewall port(if svnserve)

Also to consider are benefits/disadvantages to having multiple projects in one repository vs. one project per repository. The revision disparity isn't much of an issue, but excessive time to get the log might be if multiple projects are in one repository, however, is this offset by easier user administration?