Hi, chmilz,
It is easy to be overwhelmed with too many options to shop from for what you need. Here is what I suggest, though:
OneDrive
Yes, that's what I recommend. I have years of SecondCopy, SyncPro, Dropbox, SugarSync, and several others, syncing to several locations (outside my network) and to PCs and Mac computers, servers, and smartphones. Some of these were scheduled syncs, some 24/7 syncs (like Dropbox), and some were on-demand.
But I think OneDrive does it right. I think three things will save Microsoft: Xbox, Surface, and OneDrive. Office will sustain them, but these things will save them.
The best thing to do is to make sure your documents to sync (share), are under the Documents location of your PC and your Surface Pro 2. Then, if both computers are configured to logon to OneDrive, the files will sync. To add your music collection (MP3, WMA, etc.), copy or move them to your Music location under Documents.
By the way, you can right-click on the Documents location, and choose "Location", to specify where you want all your main data files (not software, but data). I have all mine on a 64GB SD card on my Surface, and on the C:\Documents folder on my PC. My music collection is 180 GB (really), and I don't sync it between PCs, but I do on my Mac computers.
Here is some
information about OneDrive that should be helpful.