It's a laptop, isn't it? You'd have to dismantle the entire laptop to get to the cmos battery and then have to put it all back together again, a big job that could end up making the situation worse. It's not a good idea to remove the cmos battery in a laptop.
It's not the processor, it's the cd/dvd drive or your disks that you are using. It's possible that the disk you are using are copies and when you had them burned, Multi-
Session had not been disabled prior to burning so those disk are not usable in any computer other than where they were burned.
It could also, or either, be that the disk types are one of those +r or -r formats that is different to the CD or DVD drive that might be usable without the same format type (rare but can cause read or boot errors).
Is there any hdd in the laptop?
Is there a previous OS on the hdd?
Can you access the current OS (if there is one), boot to desktop?