Maintanance concerns

I just got a 1990 corolla DX with 120,000 mi for real cheap. The car shakes pretty good at a stand still and can really feel the engine chugging in the pedal while hitting the gas. I also hear a pretty noticable tapping from under the hood. Should i be concerned? I also dont know when the radiator and trans was last flushed and filled or when the distributor and wires were last replaced. Is the distributor eay to replace and is it important? Thanks to all who respond!

The distributor is a no-brainer to replace. Easiest thing ever. YES YOU SHOULD BE CONCERNED! Go and get your timing belt replaced NOW!

Actually i just drove the car again and it now is loud and sounds more like a chevy and doesnt really viberate. Still timing belt? thanks

Timing belt or some serious knock it sounds like. Either way - BAD. Take to mechy ASAP.

yea, get the timing all checked out and the cam belt, make sure it has fresh oil also.

OK, "Oz" might be right about your t-belt (especially with a used car with 120,000) as a safe measure against future performance problems.
However, the tapping sound under your hood cannot be easily diagnosed over the i-net. It could be any number of things that are happening. As suggested, it might be some serious "knocking", which means your gas/oxygen mix is not at the proper ratio, creating combusiton related problems at the valves as you step on the gas pedal - hence the sluggish acceleration.
The added vibration might be asociated with worn motor mounts/brackets. Your vehicle probably has three. I needed my mounts replaced at @200,000 miles. No, it was not cheap, but it was definitely needed.
The best peice of advice since it is a used vehicle; Take it to a trusted mechanic, or save some money for a 1-2 hour diagnostic at a dealer.