Ok...

I have an ATI X300 graphics card (Yuck I know, but it came with my dell PC so Im pretty sure replacing it is either impossible or will cause me more issues).

Basically, over the past couple of days anytime I run missions I seem to run into this issue where my pointer starts bugging out and I can't select doors or elevator panels. Body parts seem to go invisible or see through and I either eventually crash out of MxO or my PC crashes.

Any Ideas?

I've tried re-installing drivers, using driver cleaner and deleting any existing old drivers to make sure there's nothing from previous drivers conflicitng.

Upgrading a video card in a laptop

You should be able to upgrade to a ATI Mobility Radeon X2300  (depending on the form factor of your existing card and whether or not the X2300 will fit)

It sounds like your card is having heat failure. Is the fan on the card working? Are the air vents clear and not blocked by what the laptop is resting on?

As for upgradability most Dell's are upgradable these days, ever since they purchased Alienware. In fact Dell are starting to produce some decent gaming machines thanks to Alienware's influence.

Well, it's a PC not a laptop, however, I haven't actually cleaned the inside in a while, that could be it right there ~_~

Thanks for the help and suggestions I'll clean it out properly tommorow and see what the result of it is.