there were a few years of bad capacitors ... some would go in months. i still have boards laying around with that problem i couldnt warranty for reasons unknown. if you made it this long, consider yourself lucky.
as for whether it will die sooner or later, tough to say. depends how critical them capacitors are. most are way under used because most users don't task their computers to full potential and definitely not for long periods. yours though, being old will be stressed more by games and internet flash programs and heat.
anyway, theres two options.
1. buy an identical board on ebay. cheapest option and simple.
2. upgrade. a 'standard' pc upgrade right now is about $250.00 (new board, 2GB ram and processor) then i would charge about $75-$100 to transfer windows to new hardware. typically this is lossless in terms of installed software.
rarely a new power supply is required and recently a chance you will need a new cdrom ($35) as there are few IDE ports replaced with SATA. some don't even have floppy connectors.
anyway this is a motherboard problem so you don't need to panic and backup all your stuff as you wont lose it if it dies, it will all be on the hard drive. you should though have backups incase of HD failure but no need to panic at this moment.