The iPod 20 or 30 is good for you if you want to have all your music with you at all times. If you don't need that, you could go with the shuffle (or the mini) and have just a portion with you at any time. But I think that once you get used to being able to listen to anything whenever you want, you'll really appreciate it, so I'd suggest getting the 20 or 30. Or the mini.
You might be better going with the 20 gig iPod, or if you really want the color/photo option, getting the 30 gig photo. It doesn't sound like you have enough music to warrant the added expense of the 60 gig iPOd, and the 20 or 30 gig will suit you just fine. With 70 albums you'll have about 2-3 gigs of music, and still have gobs of room for your *ahem* downloaded music in the forseeable future. You could get the mini, which is inexpensive and small, but only holds 4-6 gigs. That means you'd have enough for your current collection, but no room to expand on the portable if your music collection increased. Which it will as soon as you get an iPod.
Do not get a Shuffle. The Shuffle is for suckers and Apple fanboys who don't know what the other options are.* If you want to get a low cost, low capacity, solid-state (flash) MP3 player, look for something like from Creative or Sandisk.