My TI Nspie CAS calculator is restarting frequently

Natively it is unable to factor out polynomials. It does not have a CAS (Computer Algebra System). You may have confused it with some other CAS-enabled calculator.

During operation of the TI-Nspire handheld it may be necessary to reset the device. Circumstances which may require a reset include; keys not responding, device will not turn on or a garbled display. To reset the device:
• Remove the keypad (for TI-Nspire with ClickPad, TI-Nspire with TouchPad, and TI-Nspire CAS with Touchpad) or the battery door (for TI-Nspire CAS with ClickPad) and remove at least one battery from each column of batteries. After 2-5 seconds, reinsert the batteries but do not turn the handheld on.
For the TI-Nspire and TI-Nspire CAS handheld units with ClickPad:
• Hold down [home] [enter] [P].
• While holding these keys press [on].
For the TI-Nspire and TI-Nspire CAS handheld units with TouchPad and the TI-Nspire CX and TI-Nspire CX CAS:
• Hold down [doc] [enter] [EE].
• While holding these keys press [on].
Please Note: For TI-Nspire Family handheld units that contain rechargeable batteries you can alternatively hold the above keys while pressing the [reset] button on the back of the handheld rather than removing the battery for 2-5 seconds.
• The device will boot up as in the previous reset, but will display a menu with the following options. Please try options 2, 3, and 4 in that order.
• 1: Cancel - The most non-intrusive reset option; no changes are made, the unit restarts.
• 2: Delete Operating System - The operating system will be deleted without deleting any documents on the system.
• 3: Delete Document Folder Contents - This will delete the user's documents, but will not delete the OS. Selecting this option is the same as using the RESET hole on the back of the unit.
• 4: Complete Format - This will delete the OS and all documents for a total wipe of the handheld.
Please note that the second and fourth option will require that the OS will need to be reinstalled

Some calculators that have a CAS (computer Algebra System) are the following
TI Nspire CAS, TI CX CAS, TI92 and TI 92 PLus, TI 89 Titanium, TI Voyage 200 PLT.
Casio FX Algebra 2.0 PLus, Casio ClassPad 330, 330 PLus, 400
HP 48 G, G+, GX, 49 G+, 50 G

its round has lots of squares and has a handle

The TI 86 calculator does not manipulate algebraic expressions. If does not have a Computer Algebra System or CAS. Try the TI 89 Titanium, TI92/92PLUS, Voyage 200 PLT, TI Nspire CAS, TI Nspire CX CAS. In Casios you have the ClassPad series (300, 300Plus, 330 Plus and the latest 400. The ClassPad 400 has a color screen. It is also orientable portrait or landscape. Other Casios are the Algebra FX 2 and 2, and the FX 9860 G Plus/ SD. In HP you have HP 50G, HP49C, HP49G+.

The calculator does not have a Computer Algebra System or CAS: It cannot handle non numerical quantities. Every letter symbol must have a value stored in it prior to being used. If no value is stored in a letter symbol, value 0 is assigned to it. Sorry.
As to calling Pi a variable, I would not got that far, even if the calculator would give me 2Pi.
TI calculators that have a CAS are the TI92 Plus, the Voyage 200 PLT, and the TI Nspire CAS, TI Nspire CX CAS.

The TI Nspire has two calculation modes: Auto and Approximate. In Auto mode the calculator will attempt to do exact calculations. If that is not possible then the results are displayed as decimals. The non CAS version does not do symbolic manipulations, only the CAS version can do that.
However if you are actually using the CAS calculator, then go to the settings ( Settings>General ) and change the settings for the calculatoion mode to EXACT. The Non Cas does not have that third choice.

No, your calculator cannot factor polynomials. You need a calculator that has a CAS (computer Algebra System)
Yes Casio sells calculators with CAS: The FX-Algebra 2.0 and 1.0, the FX-9860GPLUS/GII SD, the GRAPH85 or 80 and the Graph 100+. You also have the CLASSPAD Series 300PLUS and 330.
TI and HP also have CAS calculators.

Texas Instruments
TI 89 /Titanium, Voyage 200PLT, TI92PLUS (discontinued), TI Inspire CAS.

Hewlet-Packard
HP 48G/G+/GX, HP40G, HP49G/G+ and the top of the line HP50G

Sorry, but you cannot calculate limits of functions with this calculator. It does not have a Computer `Algebra System (CAS). For that you need a graphing calculator with CAS: Casio ClassPad 300, 300PLUS, 330, HP 48 GII, HP49 G/ G+, HP 50G, TI-NSPIRE CAS, TI89 Titanium, TI 92/92PLUS, TI Voyage 200 PLT. It is still a very good scientific (non graphing) calculator
However, you can calculate numerical derivatives, and numerical integrals, solve linear and non-linear equations.

Even though this post does meet your expectations, do not let that prevent you from rating it.

You cannot do it with this calculator. It does not have a Computer Algebra System (CAS). Try a TI89 Titanium, a TI 92PLUS, a TI 200PLT or a TI-Nspire CAS.
However, they may exist other programs on education.ti.com or ticalc.org. Search these sites and you may be lucky.