Illegal Peformance Shut Down Problems & Low Resources On Windows 98

My Computers Resources Drop To 0% & Then It Goes To The Blue Screen & I Have
To Restart, Sometimes It Freezes & I Have To Use The Shut Down Button. My
Second Problem Is That For Almost Every Window I Open A Window Saying,
"This Program Has Performed An Illegal Search & Well Shut Down," & At Very
Bottom It Say If Problem Presists Contact The Vendor. Sometimes Those Windows
Open One After Another & My Computer Freezes Or It Goes To The Blue Screen.
Then I Either Shut It Down With The Button Or Restart It. If Anyone Knows
What I Could Do To Fix It, Let Me Know.