I have and use a 2006 MacBook Pro 17" which Apple treats in a bizarre way. Latest version of Mac OS X works on it fine as do things like Photos (which sucks but that's another story) and iTunes.
But they don't support the hardware. It is considered (their word): obsolete. The battery died long ago (Apple actually replaced it once years ago when it swelled up) and needs replacing (the replacement battery also swelled up) and they won't replace it.
I also have a MacBook Pro 17" with a swollen battery (a bit newer though: early 2009)
Did you try having the battery fixed by a 3rd party? I remember a few years ago I mailed a broken Powerbook battery to some guy who replaced the cells. I think it was a a NiMH battery, but maybe it works with lithium-ion batteries as well?
I have a 2008 MBP 17" that's also gone through two swollen batteries. Most of the time now I use my work-provided Lenovo, but every now and then I need a big screen and Adobe Creative Suite (with a still-kicking Wacom Graphire2 tablet, circa 2003), so out comes the Macbook.
But they don't support the hardware. It is considered (their word): obsolete. The battery died long ago (Apple actually replaced it once years ago when it swelled up) and needs replacing (the replacement battery also swelled up) and they won't replace it.