Thats completely fine with me as long as I can CHOOSE the resolutions and maybe customize them as well and since iPad 3 display is perfectly capable, hope that the App can scale that Host Desktop resolution to the Retina Display.
Please list & share experiences of RDP/VNC client / Remoting Apps to log in host desktop at custom high resolutions & scale to display on iPad Retina?
You can customise any resolution up to 2048x2048 with Pocket Cloud.
That's it running 1536x2048 for portrait mode.
In answer to your other question RDP is Remote Desktop Protocol. I prefer this over standard remote solutions for many reasons, not least of these being that I can log in and use my PC in the background on my iPad and still use the PC as normal whilst logged in. Although unless your running Windows server you do have to enable a tiny hack to get multiple log-ons enabled.
In terms of ease of use that depends on the client you use. For the connection itself Logmein wins hands down, which is why I think most people use it, it's very noob friendly. I myself use it from time to time depends what I'm doing, as it's free now there's no harm in having it on there as well. To connect with Pocketcloud there's a Auto discovery option that uses a google account to connect you to your PC which worked pretty well the one time I tried it (I personally don't use it). This gets you around the problem of being on a Dynamic IP address (if your ISP supplies you with a dynamic IP it'll change every now and then) Logmein does this automatically as it reports your IP to their servers then you log in via their software.
As for ease of use once your connected, in my opinion PocketCloud is easier to use, the whole experience is a little more fluid, it's without doubt at least AS easy to use as Logmein.
There is a free edition of PocketCloud available on the app store but from what I remember it restricts the resolution to something quite small. So what I'd suggest is download it and see if you can connect have a little play with it and then buy the full version if you find you like it.