As far as "standalone" players go your best bet is really just getting a damn XBox and modding it. Standalones currently are spotty on support for many new codecs, and I can't think of one that's capable of handling OGM or MKV file formats. It wouldn't be a problem if they could upgrade, but as far as I know none can. A modded XBox has no such limitations, has overscan compensation (so the edges of the picture don't get cropped if you don't want them to) and in general kicks a lot of ass.
Now as far as converting to a CD that can play in a DVD player... the difficulty is that the formats you're describing -- VCD, SVCD, CVD and miniDVD -- don't have universal DVD support unfortunately. Most DVD players support VCD, slightly less support SVCD and CVD, and very few seem to support miniDVD. There's a non-standard format in use called KVCD -- technically a type of XVCD -- which is supported on many DVD players, and if your player can do it that's the format I recommend. The best way to find out what your player supports is to look it up on videohelp.com. (Except for KVCD. The idiots over there think it's a "fringe" format, even though there are KVCD releases of everything that crosses vcdquality's lists)
As far as making any of the formats listed, it can be done entirely with freeware/shareware tools. I'd list them all and how to do it, but it differs for each one and it's usually not simple. However, let me give you some of the perks of each.
VCD: Widely supported by DVD players, but part of the standard is that it's Constant Bitrate, meaning the video looks fine at one point, then turns to crap if any complex images come on screen. Audio is limited to one single bitrate: 224kbps mp2. The end result is that you can only fit 74/80 minutes of content onto a VCD, period.
SVCD: Supported by many DVD players, but not all. It's a funky resolution -- 480x480 -- and since that's not a DVD-compatible resolution a lot of DVD players don't have support for it. (VCD's resolution is DVD compatible) The quality is a lot better and it allows for Variable Bitrate encoding and a wide range of audio bitrates, but because of the high resolution you'll only be able to fit about 50~60 minutes of decent-quality fullscreen video onto on CD.
CVD: Basically the same as SVCD, but with a DVD-compliant resolution. (352x480) Somehow it has less support among DVD players though, but usually if your player supports SVCD it supports CVD. (and sometimes even if your player doesn't support SVCD) Because of the lower resolution it's possible to fit more video onto a CD at the same quality. I've seen examples of people fitting full-length (letterboxed) films onto one CD using CVD.
miniDVD: All this is is a DVD authored on a CD instead of a DVD. Unlike all other formats listed here a miniDVD/cDVD is burned in mode 1 rather than mode 2/XA, meaning that you can only fit 700mb of content on a disc, rather than 800mb. This may have something to do with why it isn't widely accepted by most DVD players. On the plus side, you can use all the formats and tricks allowed on DVDs, namely Variable Bitrate encoding, expanded GOP structures, AC3 audio and selectable subtitles. There are low resolution video formats which are usable on DVD, so it's quite possible to fit 2 hours of content on a 700mb miniDVD. It's just a trick-and-a-half finding something that can read it.
(S)KVCD: KVCD isn't really a standard, in fact it's non-compliant with any known specification. (Video is technically DVD-compliant, which may help) However, a lot of DVD players are capable of playing it, about as many as are capable of handling SVCDs. KVCD uses three things to fit more video onto a CD: Variable Bitrate encoding, a modified GOP structure (meaning keyframes occur less frequently) and a modified Quantization matrix. (Which makes any "noise" in the file much less noticable) You can also use just about any bitrate audio you wish. The end result is that you can fit 2 hours of content onto a KVCD with no noticeable drop in quality. This is the format I use most of the time, as all my/my family's/my friends' DVD players can handle KVCDs.
There are plenty of guides out there as to how to make all of these formats. If you want some help you can PM me, but I won't be here for about a week, assuming wildfires haven't blocked our desired path of travel once again.