Have you downloaded the instruction manual for Reaper?
I use ASIO4ALL with Reaper and it travels along on my Vista 32-bit OS without a hitch. I also prefer to use theme Options | Themes | Default_3.0
because I personally find it easier to see the VU meter in the Mixer.
I suggest that you don't install Ozone yet. Wait until you have Reaper up and working and you're feeling comfortable with it. Ozone only gives you 10 days to try it out and it would be a shame to not maximize those days because of still learning a DAW.
Below are the settings I use - found under Options | Preferences | Audio | Device
- The Audigy 2 ZS is my external soundcard that I use for both inputs and outputs.
- I did nothing to configure the ASIO settings under "ASIO Configuration".
If your Reaper experience is destined to be anything like mine, it will take a couple of weeks for you to start feeling comfortable with the DAW. It's incredibly powerful and there's an awful lot to get one's head around. What I did was to download the file "All Through The Night.RPP", progressively work my way through the User's Guide, and follow all the instructions in the Guide about how to modify "All Through The Night" in the many described ways.
P.S. It's probably better to take this discussion over to the "Off Topic" forum. It's likely to get lost in this thread.