iTunes Match won't match songs I didn't buy on iTunes

I have a modest 4000+ song library, most of which came from CDs ripped to iTunes. I have an old Acer Aspire desktop (3GB RAM, AMD Athlon 64 3800+, Vista Basic) that is a fairly terrible computer but it works, mostly. The reason I want to move all my tunes to Match is that I do want to buy a Mac in the near future and it would be nice to have my songs already saved to the cloud instead of dealing with the hassle of transferring them over manually. It seems like the kind of thing that Match exists for! But... the ONLY songs I can get to match are those I bought from iTunes... a whopping 62 out of my 4000+ songs! I rebuilt the library, did nothing. I removed all of my songs from iTunes... that at least got it to match the 62 I purchased from iTunes. I tried adding in all my songs at once, wouldn't match (keeps freezing during or at the end of Step 1), I took them umatched songs back out and added a single album (12 songs), froze again. I took that album out and tried adding my REM albums, figuring that it had to recognize those... froze again.

I tried one REM album... it seems to have worked (as I was typing this) but when I look in iTunes though it said I have 76 songs now matched there are no cloud icons next to the songs I just added. So I don't know if it worked or not.

Is there some trick I'm missing to get it to add more than one album at a time? Is it my apartment's somewhat suspect wifi network (not exactly broadband speeds), my crappy PC, all of the above and I'm doomed to adding an album, matching, waiting, banging head on desk... etc.? And why no cloud icon at all for the supposedly "matched" songs? I don't want to lose almost 99% of my music from my iPhone by turning on matching on it if this isn't working!