When you first install Reaper on Windows, it'll be using the Wave Out audio system for maximum compatibility out of the box. Trouble is, Wave Out is a super old protocol and it doesn't cope well with today's low latency expectations, so if you're planning to monitor yourself during recording in Reaper and you don't have an interface with an ASIO driver, this cheat sheet aims to get you up and going with the next best thing (Wasapi from Microsoft). I'll walk you through setting up Wasapi best I can without having ever used your exact combination of hardware. Just so you know what you're getting into, Wasapi can be a bit of a finicky beast to get configured initially because for some reason, Microsoft's default settings prevent Microsoft's own audio protocol from working (infinite face-palm), but follow these steps through and you should be good to go.
Note: all of the below assumes you're confident doing a bit of tinkering with Windows. If that's not the case yet, I can provide one-on-one support to getcha going for a very reasonable rate. Feel free to hit me up on scottchesworth@gmail.com if that's of interest.

start by trying this:
1. In Reaper, go into Preferences, Device category.
2. Set Audio system to "WASAPI (Windows 7/8/10/Vista)", hit Tab once, and set it to "Shared mode". That "Shared mode" setting is what's going to enable Reaper and your screen reader to use your audio device at the same time, albeit perhaps with a little persuasion.
3. The next two choices are input and output devices. I don't know the exact names of what you'll find there because I've not used your hardware, but you should choose entries that mention whichever device you intend to use.
4. If you're intending to record a single mono vocal, you can eliminate some variables further down the line by setting "Input channels" to "1". You'll probably always want stereo playback though, so leave "Output channels" set to "2".
5. Tab once more to set your block size. I usually start with 128 here, see what that performs like, and if it's not taxing the machine too much I go back in and reduce it to 64 later.

That's it in Prefs for now. Tab to the OK button or just hit Enter. Don't be alarmed if Reaper complains that it couldn't open the audio device the first time you try this configuration, just follow the next set of steps to fix Microsoft's stupid default settings.

1. Close Reaper for now.
2. Go to the Run dialog (Windows+R), type in mmsys.cpl and hit Enter. this will take you into the Sound applet of Windows Control Panel.
3. Find your audio device in the list of Playback devices, hit Tab until you find the "Properties" button, and hit Space on that.
4. In the Properties dialog, switch to the "Advanced" tab. In there, you need to check and likely change two things:
A) Select the sample rate and bit depth to be used when running in shared mode in the first combo box. If you have this choice, "2 channel, 24 bit, 44100 Hz (Studio Quality)" is a safe bet.
B) Make sure that the "Allow applications to take exclusive control of this device" option is unchecked.
Once done, hit OK and you'll land back in the Sound applet.
5. Now switch to the Recording tab, find your audio device again, repeat steps 3 and 4. It's vital that those settings on the Advanced tab of the Properties dialog match, that's what's going to fix the error Reaper through up earlier.

Once you've done all that, reopen Reaper and retest recording. I reckon you'll be good to go, but if not, you know where to find me.

Hope it's useful!

Scottchesworth@gmail.com if it's not quite useful enough. :)