Wisdom of switching from Windows to redundant linux boxes for DHCP servers? [closed]

We've had a few issues with our Windows DHCP server failing. I'm a linux guy by nature, but not a systems guy (I'm a programmer who happens to be running IT for ~800 users), but I'm curious: how crazy would it be to just set up a couple of linux boxes to be redundant DHCP servers, either with a split scope or with some of them set up as failovers.

If we go that route, what specs are needed for a box to simply act as a reliable DHCP server?

I'm imagining we could commit these computers to acting only as DHCP and leave our Windows server as an AD controller, a fileserver, etc. Our organization has lots of users who just need wireless to work, so having DHCP reliable even when the Windows server down would be a major benefit -- my gut is that it shouldn't be hard to set up some computers to just do DHCP + DNS and do it well, but consultants I've talked to have warned us against it in the past, so I'm curious what serverfault thinks.

Those days DNS and DHCP are really tightly linked to Active Directory. That beeing said there are people who really do this in production.

You don't need anything particular for setting a DHCP box on linux: any box can do the trick.

These days, for AD, I'd recommend using Windows Server 2012 and the High Availability DHCP feature and install on a pair of servers (or domain controllers). There's no need to go to ISC DHCP on Linux for this.