A500 failing?

[hotdiggity]

Well, tonight I pulled the ol' Amiga 500 out of the closet. It's been a few years since I powered it on. Unfortunately, it appears that the internal disk drive is failing -- it will start to read, like it recognizes that a floppy has been inserted, but then it stops after a few short noises. The insert-floppy screen goes away, then comes back after a bit. This happens with pretty much any floppy. Occasionally it will get to a flashing red and black screen that says software failure.

I'm also getting weird graphical glitches/artifacts on my screen (see attached). This happens both through the B&W RCA output and color video out via my A520 adapter. I don't have an actual monitor anymore.

Does anyone know what's going on?