The bad news is, you can't straight up swap drives. The optic drive, like on the 360, is paired with the motherboard, you'd have to either flash the new driver board or swap driver boards or something like that. As far as I know, when it comes to PS3, this is less walked territory, unlike on 360 where there's a lot of tools.
You can swap driver boards into an entirely new optic drive (the models would have to match exactly for this to never have issues). There's a video of someone doing it here:
http://youtu.be/Pfng7G9Yhzs (Note, this shows a PS3 Slim drive, but the process should be very similar)
If you want to flash Firmware, you're really on your own.
If it's the laser, you can replace that (it's not terribly difficult, just take your time, there's a video of someone doing it here
http://youtu.be/D6dnzE6rpK4) And that assembly piece is only $35 or so. If all that's wrong is the laser is not functioning, this is what you should do.
If the Driver board itself is malfunctioning, you're SOL unless you can flash firmware.
Is it worth fixing it? Maybe. Maybe not. Depends on what you want. If you want to buy an entire new PS3, that's up to you.
Personally, I'd buy a new one, and I'd fix this one. I would find the least reasons to boot up a BC PS3 as possible, to try to preserve that machine. Fixing a broken solder joint on surface mounted chips is not easy at all, and to do it properly requires very expensive equipment and a lot of knowledge about profiles.
It's not something I'd want to, personally, do. (FYI, there is a guy on eBay whom does it for $150 or so plus shipping, and he will live stream his progress to you. He has extremely expensive professional equipment and professional engineering training. So, it can be fixed, if that ever happens.)
